Compounds having growth hormone releasing activity

ABSTRACT

Compounds that promote growth hormone releasing activity are disclosed. These compounds have the formula:  
     A 1 -A 2 -X; A 1 -X′; or A 1 .-Y  
     These compounds can be present in a pharmaceutical composition. The compounds can be used with a second compound that acts as an agonist at the growth hormone releasing hormone receptor or which inhibits the effects of somatostatin. These compounds can be used for a variety of uses such as treating hypothalamic pituitary dwarfism, osteoporosis, burns, or promoting wound healing.

FIELD OF THE INVENTION

[0001] This invention relates to novel compounds that promote therelease of growth hormones when introduced to animals, preferablyhumans, and methods of use thereof.

BACKGROUND OF THE INVENTION

[0002] The elevation of growth hormone (GH) levels in animals, e.g.,mammals including humans, upon administration of GH-releasing compoundscan lead to enhanced body weight and to enhanced milk production ifsufficiently elevated GH levels occur upon administration. Further, itis known that the elevation of growth hormone levels in mammals andhumans can be accomplished by application of known growth hormonereleasing agents, such as the naturally occurring growth hormonereleasing hormones.

[0003] The elevation of growth hormone levels in mammals can also beaccomplished by application of growth hormone releasing peptides(GHRPs), some of which have been previously described, for example, inU.S. Pat. Nos. 4,223,019; 4,223,020; 4,223,021; 4,224,316; 4,226,857;4,228,155; 4,228,156; 4,228,157; 4,228,158; 4,410,512; 4,410,513.

[0004] Antibodies to the endogenous growth hormone release inhibitor,somatostatin (SRIF) have also been used to cause elevated GH levels. Inthis latter example, growth hormone levels are elevated by removing theendogenous GH-release inhibitor (SRIF) before it reaches the pituitary,where it inhibits the release of GH.

[0005] These methods for promoting the elevation of growth hormonelevels frequently involve materials which are expensive to synthesizeand/or difficult to isolate in sufficient purity for administration to atarget animal. Low molecular weight, relatively simple and inexpensivecompounds that have the ability to promote the release of growth hormonewould be desirable in that they could be readily and inexpensivelyprepared, easily modified chemically and/or physically, as well aseasily purified and formulated, and designed to have improved transportproperties.

[0006] GH and/or GHRPs have been administered to stimulate growthhormone production and/or release, for example, to stimulate growth,enhance milk production, enhance body weight, increase rate of proteinsynthesis, reduce rate of carbohydrate utilization, increasemobilization of pre-fatty acids. Although the use of many of thesecompounds such as a series of short peptides (e.g., U.S. Pat. Nos.5,663,146 and 5,486,505) have been important steps in the design anddelivery of compounds having GH and/or GHRP properties, improvements canstill be made. For example, improvements can be made in the areas oforal bioavailability, serum retention time, etc.

[0007] Non-peptidal or hybrid-peptidal secretagogues have also beendescribed. See U.S. Pat. Nos. 5,494,919; 5,492,920; 5,492,916;5,622,973; WO95/ 13069, WO96/ 15148; WO96/35713; WO97/22367; WO97/00894;WO97/07117; and WO97/ 11697. Despite the general descriptions of suchcompounds, it is not possible to make broad generalizations about whichparticular compounds are favorable. Although some secretagogues, whichcan promote the release and elevation of growth hormone levels in theblood, have been described, corresponding data on the biologicalactivity has often been lacking. Moreover, even in terms of tripeptideswith or without C-terminal modifications, the data suggests that it hasheretofore been impossible to make the broad sweeping generalizationmade in those publications about what would or would not be a favorableamino acid combination at the three positions of a tripeptide holdingthe C-terminal constant or holding the peptidal portion constant whilemaking changes, or changing the chemical moieties added. Changes in anyof the constituents can have great effects on activity. It is submittedthat these references do not lead to general teachings of biologicalefficacy.

[0008] In order to maximize the ability to select and tailor a compound,it would be desirable to have a class of compounds that generallyprovide good growth hormone releasing effects and have at least oneother desirable biological activity such as better bioavailability,absorption, metabolism, pharmacokinetics, excretions, etc. It would alsobe desirable to have compounds which can promote the release andelevation of growth hormone levels in the blood of animals, particularlyin humans, to be able to use such compounds to promote the releaseand/or elevation of growth hormone levels in the blood of animals andhumans, and to provide methods for promoting the release and/orelevation of growth hormone levels in the blood of animals using suchcompounds.

[0009] The aforementioned discussion illustrates that a broad chemicaldiversity of synthetic GHRPs ranging from peptides to partial peptidesto non-peptides. Overall, the peptides and partial peptides have beenthe most effective in promoting elevated growth hormone levels. Forexample, partial peptides consisting of natural and unnatural aminoacids of different chain lengths and C-terminal amide groups or asubstituted amide with various organic chemical groups. Resultspublished as early as 1982 stated that certain GHRPs with only 3-7 aminoacids released GH and that having a D-amino acid at certain positionswas useful. From 1982 to the present, GHRPs with more potent GHreleasing activity have been developed. This research taught thatcertain amino acid positions could have certain substitutions but notothers, and that one amino acid residue could affect what othersubstitutions could be made.

[0010] Until compounds having the optimum physical-chemical propertiesand physiological-biological actions and effects are discovered forvarious diagnostic and therapeutic uses in humans, it is important todiscover a general chemical approach that will result in new types ofGHRPs. Such a broader GHRP chemical base will make it possible to betterimplement and refine the GHRP approach.

[0011] Properties of GHRPs that are important include that they areeffective when administered orally. In addition, the compound shouldaugment the normal pulsatile physiological secretion of GH. In somesubjects with decreased GH secretion, GH can be replaced in aphysiological way. Physiological replacement of a hormonal deficiencyimproves health while minimizing the potential adverse action of thehormone. This is especially important in treating older men and women,as they may be particularly susceptible to the adverse effects ofover-treatment with GH. Already, chronic administration of GHRPs toanimals and humans has produced anabolic effects. Body weight gain hasbeen increased in rats, milk production has been increased in cows.Additionally, when a compound such as DAla-DβNal-Ala-Trp-DPhe-Lys-NH₂(GHRP-2) was administered to short-statured children with variousdegrees of GH deficiency 2-3 times per day over a 2 year period, therate of height velocity has been accelerated in those children.

[0012] In principle, the anabolic biological effects of GHRPs emphasizethe potential clinical value of the GHRP approach. The finding thatGHRP-2 is less effective on height velocity than usually obtained withchronic recombinant human growth hormone (rhGH) administration,underscores the desirability for improving the GHRP approach. Thisincludes further optimization and extension of the range of the GHRPchemistry in order to produce more effective biological actions.

[0013] In looking at these compounds, one looks at a varied series ofbiological effects such as the duration of action of GHRP. Otherparameters that may substantially be affected by the chemistry of theGHRP include desensitization of the GHRP GH response, actions on thehypothalamus, effects on SRIF release and action, effects on ACTH andPRL release as well as possible effects on putative subclasses of GHRPreceptors. All of these actions are directly and/or indirectly dependenton the GHRP chemistry, pattern and efficiency of oral absorption as wellas the metabolism and secretion of the particular GHRP.

SUMMARY OF THE INVENTION

[0014] We have now discovered a new group of compounds (sometimesreferred to as secretagogues) that provide desirable in vitro and invivo growth hormone releasing activity and have at least one otherdesirable biological activity such as increased retention time. Thesecompounds have the following formulas:

A₁-A₂-X  Formula I:

[0015] wherein

[0016] A₁ is Aib (aminoisobutyric acid), inip (isonipecotyl) or ABU(aminobutyric acid). The Aib residue can be substituted orunsubstituted. Preferred substituents include C₁-C₆ alkyl and halogens.Aib is preferably unsubstituted. Aib is preferably αAib. ABU ispreferably γABU or αγABU, more preferably α,γABU;

[0017] A₂ is any natural L-amino acid or Pal, or their respectiveD-isomers, DαNal (α-naphthyl-D-alanine) or DβNal (β-naphthyl-D-alanine),preferably A₂ is DTrp, DαNal (α-naphthyl-D-alanine) or DβNal(βnaphthyl-D-alanine), more preferably A₂ is DTrp or DαNal;

[0018] X is

[0019] (1) R₁-R₂-Z, wherein R₁ and R₂ are any natural L-amino acid, Pal,αNal, βNal, DβCl, CHx, where CH_(x) is cyclohexyl, CHxAla, or any oftheir respective D-isomers, preferably R₁ is DPro, DTrp, DβNal or DPhe,more preferably R₁ is DPro or DTrp; and R₂ is preferably Gly, Phe, Pro,DPro, DPhe, DPal, DLeu, DHis, DVal, DGln, DArg, DAla, DSer, DThr, DIle,Arg, Orn Lys, Ala, Pal, Thr, Val, PheCHx, CHxAla or CHx, where x ispreferably 1-8, more preferably 1 to 5; and Z is CONH₂ or COOH;

[0020] (2) DpR₃Phe-R₄-Z wherein R₃ is a halogen, preferably Cl, and R₄is any natural L-amino acid or Pal, or their respective D-isomers,preferably R₄ is Phe or Arg, and Z is CONH₂ or COOH;

[0021] (3) NH(CH₂)_(n)NH, where n is 1 to 8, such as -2-aminoethylamide,-3-aminopropylamide, -4-aminobutylamide, -5-aminopentylamide, or-6-aminohexylamide;

[0022] (4) R₅-R₆, wherein RS is any natural L-amino acid, Pal, αNal,βNal, DβCl, CHx where x is 1 to 10, or any of their respectiveD-isomers, preferably R₅ is DPro or DTrp, and R₆ is

[0023] (a) diisobutylamide

[0024] (b) dipropylamide

[0025] (c) butylamide

[0026] (d) pentylamide

[0027] (e) dipentylamide

[0028] (f) C(═O) (substituted heteroalicyclic or heteroaromatic)

[0029] such as -piperidine-3-methyl-benzylether

[0030] -N-diethylnipectamide

[0031] -N-piperazine methylsulfonamide

[0032] -diethylamide

[0033] -m-methylpiperidine

[0034] -3,3-diphenylpropylamide

[0035] -4-piperidino piperidinamide

[0036] -4-phenyl-piperidinamide

[0037] -N-methylpiperazine

[0038] -2-morpholinoethylamine

[0039] -spiroindole methylsulfonamide

[0040] -pyrrolidine amide

[0041] -indoleamide

[0042] -3-piperidine methanolamide

[0043] -tropin amide

[0044] -2-aminoethylamide

[0045] -3-aminopropylamide

[0046] -4-aminobutylamide

[0047] -5-aminopentylamide

[0048] -6-aminohexylamide;

[0049] (5) DTrp Phe ArgR₇, wherein R₇ is NH(CH₂)_(n)NH, where n is 1 to8, such as -2-aminoethylamide, -3-aminopropylamide, -4-aminobutylamide,-5-aminopentylamide, or -6-aminohexylamide; or

[0050] (6) R₈-R₉-R₁₀-Z, wherein R₈ is DTrp, DPro, DαNal or DβNal,preferably R₈ is DTrp or DPro, R₉ is any natural L-amino acid or Pal, ortheir respective D-isomers, preferably R₉ is Phe, DVal, DPro, DIle, Ile,more preferably R₉ is Phe, DVal or DPro; R₁₀ is any natural L-amino acidor Pal, or their respective D-isomers, preferably R₁₀ is Lys or Arg, andZ is CONH₂ or COOH, preferably Z is CONH₂.

A₁-X′  Formula II:

[0051] wherein

[0052] A₁. is Aib, inip, ABU, IMC (imidazole carboxylic acid), Ava,4-IMA (Nα-imidazole acetic acid), βAla, Ileu, Trp, His, DβCl, CHx, orany of their respective D-isomers. The Aib residue can be substituted orunsubstituted. Preferred substituents include N- and N-,N-C₁-C₆ alkyl,halogens, N- and N-,N-2 hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyland 3-hydroxyisobutyl. Aib is preferably unsubstituted. Aib ispreferably αAib. ABU is preferably γABU or αγABU, more preferablyα,γABU; and

[0053] X′ is

[0054] (1) R₁-R₂-Z, wherein R₁. is any natural L-amino acid or Pal, ortheir respective D-isomers, DαNal or DβNal, preferably R₁. is DTrp,DαNal or DβNal, more preferably R₁. is DTrp or DαNal, and R₂. is anynatural L-amino acid, Pal, αNal, βNal, DβCl, Aib, preferably αAib, CHxwhere x is 1 to 10, or CHxAla, or any of their respective D-isomers, andZ is CONH₂ or COOH, preferably Z is CONH₂; or

[0055] (2) R₃-R₄., wherein R₃. is any natural L-amino acid or Pal, ortheir respective D-isomers, DαNal or DβNal, preferably R₃ is DPro, DTrp,DαNal or DβNal, more preferably R₃. is DPro, DTrp or DαNal, and R₄. isNH(CH₂)_(n)NH, where n is 1 to 8, such as -2-aminoethylamide,-3-aminopropylamide, -4-aminobutylamide, -5-aminopentylamide, or-6-aminohexylamide.

[0056] The organic and inorganic addition salts thereof are alsoincluded.

[0057] In an alternative embodiment the compound has the formula

A₁.-Y,  Formula III:

[0058] wherein A₁. is Aib, inip, ABU, βAla, His, Sar or any of theirrespective D-isomers. The Aib residue can be substituted orunsubstituted. Preferred substituents include N- and N-,N-C₁-C₆ alkyl,halogens, N- and N-,N-2 hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyland 3-hydroxyisobutyl. Aib is preferably unsubstituted. A₁. ispreferably Aib, inip or ABU. More preferably Aib is αAib. Abu ispreferably γAbu or α,γAbu, more preferably α,γAbu.

[0059] Y is A₂-A₃-A₄-A₅-A₆-Z′,

[0060] A₂-A₃-A₄-A₅-Z′ or A₂-A₃-A₄-Z′

[0061] wherein A₂. is A₅-A₂. or A₂′,

[0062] wherein A₅ is a spacer amino acid such as His,

[0063] A₂. is as defined above for A₂. A₂. is preferably DTrp, DαNal orDβNal. A₂. is more preferably DTrp.

[0064] A₃, A₄ and A₅ are any natural L-amino acid, Pal, αNal, βNal, Nle,Arg-DPro, DβCl, D or L (CHX), cyclohexylalanine (CHXAla), or any oftheir respective D-isomers, preferably A₃ is DPro, DTrp, DβNal or DPhe,more preferably A₃ is DPro or DTrp; and A₄ is preferably Gly, Phe, Pro,Ile, DPro, DPhe, DPal, DLeu, DHis, DVal, DGln, DIle, DNle, DArg, DAla,DSer, DThr, DIle, Arg, Orn Lys, Ala, Pal, Thr, Val, PheCHX, CHXAla orCHX. A₄ is preferably DSer, DAug, DPro, DTrp, DVal, DIle, DThr, DNVal,DNle, Ile, Pro, Phe and still more preferably, A₄ is DPro. A₅ispreferably Ile, Arg, Pal, DArg, DSer, Lys and Arg-DPro. More preferablyA₅ is Arg, DArg, and Lys.

[0065] Z′ is NH₂, OH or alkylamino or aminoalkylamino, preferably thealkylamino is NH (C₁-C₁₀ alkyl) e.g. NH(CH₂)_(n)CH₃, where n is 1 to 10such as

[0066] Ndi-(C₁-C₁₀ alkyl) e.g., Ndi-(CH₂)_(n)CH₃ such as

[0067] preferably the aminoalkylamino is a NH(C₁-C₁₀ alkylamino, e.g.NH(CH₂)_(n)NH₂ such as

[0068] N(diC₁-C₁₀ alkylamino), e.g., N [di-(CH₂)_(n)NH₂] such as

[0069] These compounds can be administered to an animal to promoterelease of serum growth hormone levels. Thus, these secretagogues can beused in a range of methods for example, to increase milk production,enhance body growth, treat hypothalmic pituitary dwarfism, osteoporosis,burns and renal failure, and to promote wound healing. They can also beused diagnostically. For example, to discover a loss of growth hormonereceptor functioning.

DETAILED DESCRIPTION OF THE INVENTION

[0070] The compounds described herein are typically easy to synthesize,have efficacy at promoting an increase in serum growth hormone levels,and are desirable for large scale production and utilization. Inaddition, these compounds may be advantageous in having physiochemicalproperties which are desirable for the efficient delivery of suchpolypeptide compounds to a wide variety of animal species because of animprovement in at least one of bioavailability, absorption, metabolism,pharmacokinetics and excretion. The preferred methods of delivery areoral, nasal and continuous delivery utilizing specialchemical/mechanical methods of delivery. Pulsed therapy is one preferredmethod of administration. These compounds have either of the followingtwo formulas:

A₁-A₂-X  Formula I:

[0071] wherein

[0072] A₁ is Aib (aminoisobutyric acid), inip (isonipecotyl) or ABU(aminobutyric acid). The Aib residue can be substituted orunsubstituted. Preferred substituents include C₁-C₆ alkyl and halogens.Aib is preferably unsubstituted. Aib is preferably αAib. ABU ispreferably γABU or αγABU, more preferably α,γABU;

[0073] A₂ is any natural L-amino acid or Pal, or their respectiveD-isomers, DαNal (α-naphthyl-D-alanine) or DβNal (βnaphthyl-D-alanine),preferably A₂ is DTrp, DαNal (α-naphthyl-D-alanine) or DβNal(βnaphthyl-D-alanine), more preferably A₂ is DTrp or DαNal;

[0074] X is

[0075] (1) R₁-R₂-Z, wherein R₁ and R₂ are any natural L-amino acid, Pal,αNal, βNal, DβCl, CHx, CHxAla, or any of their respective D-isomers,preferably R₁ is DPro, DTrp, DβNal or DPhe, more preferably R₁ is DProor DTrp; and R₂ is preferably Gly, Phe, Pro, DPro, DPhe, DPal, DLeu,DHis, DVal, DGln, DArg, DAla, DSer, DThr, DIle, Arg, Orn Lys, Ala, Pal,Thr, Val, PheCHx, CHxAla or CHx, where x is preferably 1-8, morepreferably 1 to 5; and Z is CONH₂ or COOH;

[0076] (2) DpR₃Phe-R₄-Z, wherein R₃ is a halogen, preferably Cl and R₄is any natural L-amino acid or Pal, or their respective D-isomers,preferably R₄ is Phe or Arg, and Z is CONH₂ or COOH;

[0077] (3) NH(CH₂)_(n)NH, where n is 1 to 8, such as -2-aminoethylamide,-3-aminopropylamide, -4-aminobutylamide, -5-aminopentylamide, or-6-aminohexylamide;

[0078] (4) R₅-R₆, wherein R₅ is any natural L-amino acid, Pal, αNal,βNal, DβCl, CHx where x is 1 to 10, or any of their respectiveD-isomers, preferably R₅ is DPro or DTrp, and R₆ is

[0079] (a) diisobutylamide

[0080] (b) dipropylamide

[0081] (c) butylamide

[0082] (d) pentylamide

[0083] (e) dipentylamide

[0084] (f) C(═O)(substituted heteroalicyclic or heteroaromatic)

[0085] such as -piperidine-3-methyl-benzylether

[0086] -N-diethylnipectamide

[0087] -N-piperazine methylsulfonamide

[0088] -diethylamide

[0089] -m-methylpiperidine

[0090] -3,3-diphenylpropylamide

[0091] -4-piperidino piperidinamide

[0092] -4-phenyl-piperidinamide

[0093] -N-methylpiperazine

[0094] -2-morpholinoethylamine

[0095] -spiroindole methylsulfonamide

[0096] -pyrrolidine amide

[0097] -indoleamide

[0098] -3-piperidine methanolamide

[0099] -tropin amide

[0100] -2-aminoethylamide

[0101] -3-aminopropylamide

[0102] -4-aminobutylamide

[0103] -5-aminopentylamide

[0104] -6-aminohexylamide;

[0105] (5) DTrp Phe Arg R₇, wherein R₇ is NH(CH₂)_(n)NH, where n is 1 to8, such as -2-aminoethylamide, -3-aminopropylamide, -4-aminobutylamide,-5-aminopentylamide, or -6-aminohexylamide; or

[0106] (6) R₈-R₉-R₁₀-Z, wherein R₈ is DTrp, DPro, DαNal or DβNal,preferably R₈ is DTrp or DPro, R₉ is any natural L-amino acid or Pal, ortheir respective D-isomers, preferably R₉ is Phe, DVal, DPro, DIle, Ile,more preferably R₉ is Phe, DVal or DPro; R₁₀ is any natural L-amino acidor Pal, or their respective D-isomers, preferably R₁₀ is Lys or Arg, andZ is CONH₂ or COOH, preferably Z is CONH₂.

A₁-X′  Formula II:

[0107] wherein

[0108] A₁. is Aib, inip, ABU, IMC (imidazole carboxylic acid), Ava,4-IMA (Nα-imidazole acetic acid), βAla, Ileu, Trp, His, DβCl, CHx, orany of their respective D-isomers. The Aib residue can be substituted orunsubstituted. Preferred substituents include N- and N-,N-C₁-C₆ alkyl,halogens, N- and N-,N-2 hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyland 3-hydroxyisobutyl. Aib is preferably unsubstituted. Aib ispreferably αAib. ABU is preferably γABU or αγABU, more preferablyα,γABU; and

[0109] X′ is

[0110] (1) R₁-R₂-Z, wherein R₁. is any natural L-amino acid or Pal, ortheir respective D-isomers, DαNal or DβNal, preferably R₁. is DTrp,DαNal or DβNal, more preferably R₁ is DTrp or DαNal, and R₂. is anynatural L-amino acid, Pal, αNal, βNal, DβCl, Aib, preferably αAib, CHxwhere x is 1 to 10, or CHxAla, or any of their respective D-isomers, andZ is CONH₂ or COOH, preferably Z is CONH₂; or

[0111] (2) R₃-R₄., wherein R₃. is any natural L-amino acid or Pal, ortheir respective D-isomers, DαNal or DβNal, preferably R₃. is DPro,DTrp, DαNal or DβNal, more preferably R₃. is DPro, DTrp or DαNal, andR₄. is NH(CH₂)_(n)NH, where n is 1 to 8, such as -2-aminoethylamide,-3-aminopropylamide, -4-aminobutylamide, -5-aminopentylamide, or-6-aminohexylamide.

[0112] The organic and inorganic addition salts thereof are alsoincluded.

[0113] The abbreviations for the residues of amino acids used herein arein agreement with the standard nomenclature, and are set forth below:Gly Glycine Tyr L-Tyrosine Ile L-Isoleucine Glu L-Glutamic Acid ThrL-Threonine Phe L-Phenylalanine Ala L-Alanine Lys L-Lysine AspL-Aspartic Acid Cys L-Cysteine Arg L-Arginine Gln L-Glutamine ProL-Proline Leu L-Leucine Met L-Methionine Ser L-Serine Asn L-AsparagineHis L-Histidine Trp L-Tryptophan Val L-Valine Orn L-Ornithine

[0114] Moreover, all of the three letter-abbreviations of the aminoacids preceded by a “D” indicate the dextro-isomer of the aminoacidicresidue, and glycine is considered to be included in the term naturallyoccurring L-amino acids. Other abbreviations used herein include thefollowing: Aib aminoisobutyric acid inip isonipecotyl ABU aminobutyricacid αNal α-naphthyl alanine βNal β-naphthyl alanine DαNalα-naphthyl-D-alanine DβNal β-naphthyl-D-alanine Pal 3-pyridyl alanineCHx cyclohexyl CHxAla L-cyclohexylalanine Ava Aminovaleric acid IMANα-imidazole acetic acid IMC imidazole carboxylic acid βAla β-Alanine

[0115] In one embodiment of the present invention, a group of preferredcompounds includes:

[0116] γABUDTrpDTrpArgCOOH

[0117] α,γABUDTrpDTrpArgNH₂

[0118] α,γABUDTrpDTrpOrnNH₂

[0119] α,γABUDαNalDTrpLysNH₂

[0120] α,γABUDαNalDTrpArgNH₂

[0121] α,γABUDαNalDTrpArgNH₂

[0122] αAibDTrpDTrpArgNH₂

[0123] αAibDαNalDTrpArgNH₂

[0124] αAibDTrpDTrpArgCOOH

[0125] αAibDαNalDTrpArgCOOH

[0126] αAibDaTrpDTrpArgNH₂

[0127] αAibDTrpDPheArgNH₂

[0128] inipDαNalDTrpPheNH₂

[0129] inipDαNalDTrpCHxAlaNH₂

[0130] inipDαNalDTrpPheCOOH

[0131] inipDαNalDTrpPalNH₂

[0132] inipDαNalDTrpThrNH₂

[0133] inipDαNalDTrpValNH₂

[0134] inipDαNalDNalPheNH₂

[0135] inipDαNalDTrpPheCOOH

[0136] inipDβNalDTrpPheNH₂

[0137] αAibDTrpDProGlyNH₂

[0138] αAibDTrpDProPheNH₂

[0139] αAibDTrpDProProNH₂

[0140] αAibDTrpDProDProNH₂

[0141] αAibDTrpDProDPheNH₂

[0142] αAibDTrpDProDPalNH₂

[0143] αAibDTrpDProDTrpNH₂

[0144] αAibDTrpDProDLeuNH₂

[0145] αAibDTrpDProDHisNH₂

[0146] αAibDTrpDProDValNH₂

[0147] αAibDTrpDProGlnNH₂

[0148] αAibDTrpDProArgNH₂

[0149] αAibDTrpDProLysNH₂

[0150] αAibDTrpDProDAlaNH₂

[0151] inipDαNalDpClPhePheNH₂

[0152] inipDαNalDpClPheArgNH₂

[0153] inipDαNalDTrpDProNH₂

[0154] AibDTrpDProDSerNH₂

[0155] αAibDTrpDProDThrNH₂ and

[0156] αAibDTrpDProDIleNH₂.

[0157] In another embodiment of the present invention, a group ofpreferred compounds includes:

[0158] inipDTrpDTrpPheLysNH₂

[0159] inipDβNalDTrpPheLysNH₂

[0160] γABUDβNalDTrpPheLysNH₂

[0161] α,γABUDTrpDTrpPheLysNH₂

[0162] βAlaDTrpDTrpPheLysNH₂

[0163] α,γABUDPNalDTrpPheLysNH₂

[0164] α,γABUDTrpDTrpPheArgNH₂

[0165] α,γABUDαNalDTrpPheArgNH₂

[0166] inipDβBNalDTrpPheLysNH₂

[0167] inipDTrpDTrpPheArgNH₂

[0168] AlaDαNalDTrpPheArgNH₂

[0169] αAibDTrpDTrpPheArgNH₂

[0170] αAibDTrpDTrpPheArgCOOH

[0171] inipDTrpDTrpPheArgCOOH

[0172] inipDαNalDTrpPheArgNH₂

[0173] inipDαNalDTrpPheArgCOOH

[0174] inipDαNalDβNalPheArgNH₂

[0175] inipDαNalDTrpPheDSerNH₂

[0176] inipDαNalDTrpPheDThrNH₂

[0177] inipDαNalDTrpPheGlyNH₂

[0178] inipDαNalDTrpPheGlnNH₂

[0179] inipDαNalDTrpPheDGlnNH₂

[0180] αAibDαNalDTrpPheGlnNH₂

[0181] inipDαNalDTrpPheDHisNH₂

[0182] αAibDTrpDProPheArgNH₂

[0183] αAibDTrpDProPheDArgNH₂

[0184] αAibDTrpDProDValArgNH₂

[0185] αAibDTrpDProDValDLysNH₂

[0186] αAibDTrpDProDValDArgNH₂

[0187] αAibDTrpDProDProArgNH₂

[0188] αAibDTrpDProDProDPalNH₂

[0189] αAibDTrpDProDProDArgNH₂

[0190] αAibDTrpDProDIleDArgNH₂

[0191] αAibDTrpDProDIleArgNH₂

[0192] αAibDTrpDProDProDLysNH₂ and

[0193] αAibDTrpDProIleArgNH₂.

[0194] In the above Formula I, where X is R₅-R₆ and R₆ is a C(═O)(substituted heteroalicyclic or heteroaromatic), the heteroatom isselected from the group consisting of O, N, S and P.

[0195] The heteroalicyclic moiety preferably contains 2 to 12 carbonatoms, more preferably 3 to 8 carbon atoms. The heteroaromatic moietypreferably contains 5 to 12 carbon atoms, more preferably 5 to 11 carbonatoms. Substituents include NH₂, C₁-C₁₂ lower alkyl, and as listedbelow.

[0196] Examples include piperidine-3-methyl-benzylether,N-diethylnipectamide, N-piperazine methylsulfonamide, diethylamide,m-methylpiperidine, 3,3-diphenylpropylamide, 4-piperidinopiperidinamide, 4-phenyl-piperidinamide, N-methyl 1-piperiazine,2-morpholinoethylamine, spiroindole methylsulfonamide, pyrrolidineamide, indoleamide, 3-piperidine methanol amide, tropin amide,2-aminoethylamide, 3-aminopropylamide, 4-aminobutylamide,5-aminopentylamide, 6-aminohexylamide. Preferred substitutedheteralicyclic or heteroaromatic include N-diethylnipectamide,piperidine-3-methyl-benzylether, N-piperazine methyl sulfonamide,diethylamide and m-methylpiperidine. Even more preferred areN-diethylnipectamide and piperidine-3-methyl-benzylether.

[0197] Preferably, the compound has the structure AibDTrpX, where X isDProNH₂, DPro-diisobutylamide, DProbutylamide, DPro-C(═O)(substitutedheteroalicyclic or heteroaromatic), and DTrp-Phe-Arg-5-aminopentamideand organic and inorganic addition salts thereof. More preferably, X isDPro-diisobutylamide, DPro-C(═O)(substituted heteroalicyclic orheteroaromatic) and DTrp PheArg-5-aminopentamide, and organic andinorganic addition salts thereof. Still more preferably, X isDPro-diisobutylamide or DTrp-Phe-Arg-5-aninopentamide, and organic andinorganic addition salts thereof. Even more preferably, X isDPro-diisobutylamide and organic and inorganic addition salts thereof.

[0198] In an alternative embodiment the compound has the formula

A₁.-Y,

[0199] wherein A₁. is Aib, inip, ABU, βAla, His, Sar or any of theirrespective D-isomers. The Aib residue can be substituted orunsubstituted. Preferred substituents include N- and N-,N-C₁-C₆ alkyl,halogens, N- and N-,N-2 hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyland 3-hydroxyisobutyl. Aib is preferably unsubstituted. A₁. ispreferably Aib, inip or ABU. More preferably Aib is αAib. Abu ispreferably γAbu or α,γAbu, more preferably α,γAbu.

[0200] Y is A₂.-A₃-A₄-A₅-A₆-Z′,

[0201] A₂-A₃-A₄-A₅-Z′ or A₂.-A₃-A₄-Z′

[0202] wherein A₂. is A₅-A₂. or A₂.,

[0203] wherein A₅ is a spacer amino acid such as His,

[0204] A₂. is as defined above for A₂. A₂. is preferably DTrp, DαNal orDβNal. A₂. is more preferably DTrp.

[0205] A3, A4 and A5 are any natural L-amino acid, Pal, αNal, βNal, Nle,Arg-DPro, DβCl, D or L (CHX), cyclohexylalanine (CHXAla), or any oftheir respective D-isomers, preferably A₃ is DPro, DTrp, DβNal or DPhe,more preferably A₃ is DPro or DTrp; and A₄ is preferably Gly, Phe, Pro,Ile, DPro, DPhe, DPal, DLeu, DHis, DVal, DGln, DIle, DNle, DArg, DAla,DSer, DThr, DIle, Arg, Orn Lys, Ala, Pal, Thr, Val, PheCHX, CHXAla orCHX. A₄ is preferably DSer, DAug, DPro, DTrp, DVal, DIle, DThr, DNVal,DNle, Ile, Pro, Phe and still more preferably, A₄ is DPro. A₅ ispreferably Ile, Arg, Pal, DArg, DSer, Lys and Arg-DPro. More preferablyA₅ is Arg, DArg, and Lys.

[0206] Z′ is NH₂, OH or (aminoalkyl) or (aminoalkylamino), preferablythe aminoalkyl is NH(C₁-C₁₀ alkyl) e.g. NH(CH₂)_(n)CH₃, where n is 1 to10 such as

[0207] Ndi-(C₁-C₁₀ alkyl) e.g., Ndi-(CH₂)_(n)CH₃ such as

[0208] preferably the alkylamino is a NH(C₁-C₁₀ alkylamino, e.g.NH(CH₂)_(n)NH₂ such as

[0209] N(di C₁-C₁₀ alkylamino), e.g., N[di-(CH₂)_(n)NH₂] such as

[0210] Preferred examples include moieties such as -2-aminoethylamide,-3-aminopropylamide, -4-aminobutylamide, -5-aminopentylamide, or

[0211] -6-aminohexylamide; N-dimethylamide; N-diethylamide;N-dipropylamide; N-dibutylamide; N-diisobutylamide; N-dipentylamide;N-dihexylamide;

[0212] A particularly preferred embodiment is Aib-Y, more preferablyαAib-Y.

[0213] Y is preferably A₂.-DPro-A₄-A₅-A₆-Z′; A₂.-A₃-A₄-Z′; orA₂.-A₃-A₄-A₅-Z′. Y is more preferably A₂.-DPro-A₄-Z′ or A₂,-DPro-A₄-Z′or A₂.-DPro-A₄-A₅-Z′. Still more preferably Y is A₂.-DPro-A₄-A₅-Z′. Z′is preferably -NH₂.

[0214] Preferred embodiments include

[0215] αAib-DTrp-DPro-A₄-A₅-A₆-Z′;

[0216] αAib-DTrp-DPro-A₄-A₅-Z′;

[0217] αAib-DTrp-DPro-A₄-Z′;

[0218] αAib-DTrp-DPro-A₄-Arg-NH₂;

[0219] αAib-DTrp-DPro-A₄-Arg-A₆—NH₂;

[0220] αAib-DTrp-DPro-A₄-Arg-Gly-NH₂;

[0221] αAib-DαNal-DPro-A₄-A₅-A₆-Z′;

[0222] αAib-DαNal-DPro-A₄-A₅-Z′;

[0223] αAib-DαNal-DPro-A₄-Z′;

[0224] αAib-DαNal-DPro-A₄—NH₂;

[0225] αAib-DαNal-DPro-A₄-Arg-NH₂;

[0226] and αAib-DαNal-DPro-A₄-Arg-Gly-NH₂.

[0227] A₄ is preferably DIle, DThr, DNle, DVal, DGln, DAla, DPhe, DTrp,DNVal and Arg.

[0228] Exemplery representatives of αAib-A₂.-DPro-A₄-Arg-Z′ include

[0229] αAibDTrpDProDIleArgNH₂;

[0230] αAibDTrpDProDThrArgNH₂;

[0231] αAibDTrpDProDValArgNH₂;

[0232] αAibDTrpDProDNleArgNH₂; and

[0233] αAibDαNalDProDIleDArgNH₂.

[0234] Exemplary representatives of:

[0235] αAib-A₂.-DPro-A₄-Z include

[0236] αAib-DTrp-DPro-DThr-NH₂;

[0237] αAib-DTrp-DPro-DGln-NH₂;

[0238] αAib-DTrp-DPro-Arg-NH₂;

[0239] αAib-DTrp-DPro-DAla-NH₂;

[0240] αAib-DTrp-DPro-DPhe-NH₂;

[0241] αAib-DTrp-DPro-DTrp-NH₂;

[0242] αAib-DTrp-DPro-DVal-NH₂;

[0243] αAib-DTrp-DPro-DNVal-NH₂; and

[0244] αAib-DTrp-DPro-DIle-NH₂;

[0245] Exemplary representatives of αAib-A₂.-DPro-A₄-Arg-A₆-Z includecompounds of the formula αAib-A₂.-DPro-A₄-Arg-Gly-NH₂ such as

[0246] αAib-DTrp-DPro-DIle-Arg-Gly-NH₂;

[0247] αAib-DTrp-DPro-DThr-Arg-Gly-NH₂; and

[0248] αAib-DTrp-DPro-DNle-Arg-Gly-NH₂.

[0249] Representative compounds are set forth below:

[0250] inipDαNalDTrpNH₂;

[0251] inipDαNalDValNH₂;

[0252] αAibDTrpDValNH₂;

[0253] αAibDTrpDProDSerNH₂;

[0254] αAibDTrpDProDArgNH₂;

[0255] αAibDTrpDProDPheNH₂;

[0256] αAibDTrpDProDTrpNH₂;

[0257] αAibDTrpDValDValNH₂;

[0258] αAibDValDProDValNH₂;

[0259] αAibDValDValDValNH₂;

[0260] αAibDTrpDProDLysNH₂;

[0261] αAibDProDProDValNH₂;

[0262] inipDαNalDTrpDValNH₂;

[0263] αAibDTrpDProIleNH₂;

[0264] αAbuDαNalDTrpDIleNH₂;

[0265] inipDaNalDTrpDProIleNH₂;

[0266] ipDaNalDTrpPheIleNH₂;

[0267] inipDαNalDTrpDValArgNH₂;

[0268] αAibDTrpDProDValDValNH₂;

[0269] αAibDTrpDProDProDPalNH₂;

[0270] αAibDTrpDProDValArgDProNH₂;

[0271] αAibDTrpDProDIleDArgNH₂;

[0272] αAbuDTrpDTrpDIleNH₂;

[0273] inipDαNalDTrpPheDValNH₂;

[0274] αAibDTrpDProValNH₂;

[0275] αAibDTrpDIleDIleNH₂;

[0276] αAibDTrpDProLeuNH₂;

[0277] αAibDTrpDProThrNH₂;

[0278] DHisDTrpDProDValArgNH₂;

[0279] DHisDTrpDProDThrNH₂;

[0280] αAibDTrpDProDIleNH₂;

[0281] αAibDTrpDPheDValNH₂;

[0282] αLibDTrpDProDValDArgNH₂;

[0283] αAibDTrpDProDAlaNH₂;

[0284] αAibDTrpDProDProNH₂;

[0285] αAibDTrpDProArgNH₂;

[0286] αAibDTrpDProDValNH₂

[0287] inipDαNalDTrpDProNH₂;

[0288] αAibDαNalDProDValDArgNH₂;

[0289] αAibDαNalDProDIleDArgNH₂;

[0290] αAibDTrpDProDProDLysNH₂;

[0291] αAibHisDαNalDPheLysNH₂;

[0292] αAibHisDTrpDProDValNH₂;

[0293] αAibHisDTrpDProDIleNH₂;

[0294] αAibHisDTrpDProValArgNH₂;

[0295] αAibHisDTrpDProDValArgNH₂;

[0296] αAibDαNalDProDValNH₂;

[0297] αAibDTrpDProDThrArgNH₂;

[0298] αAibDTrpDProDNleArgNH₂;

[0299] αAibDTrpDProDNValArgNH₂;

[0300] αAibDTrpDProIleArgNH₂;

[0301] αAibDTrpDProDProArgNH₂;

[0302] αAibDTrpDProProArgNH₂;

[0303] αAibDTrpDProDProDArgNH₂;

[0304] αAibDTrpDProDIleArgNH₂;

[0305] αAibDTrpDProPheDSerNH₂;

[0306] αAibDTrpDProPheArgNH₂;

[0307] αAibDTrpDProDValArgNH₂;

[0308] SarDTrpDTrpPheArgNH₂;

[0309] αAibDαNalDProDProArgNH₂;

[0310] αAibDαNalDProDNValArgNH₂;

[0311] αAibDαNalDProDIleArgNH₂;

[0312] αAibDαNalDProDValLysNH₂;

[0313] αAibDαNalDProDThrArgNH₂;

[0314] αAibDαNalDProDThrArgNH₂;

[0315] αAibDaNalDProDValArgNH₂;

[0316] αAibDαNalDProDValArgNH₂;

[0317] αAibDTrpDProDNleNH₂;

[0318] αAibDTrpDProDNValNH₂.

[0319] αAibDTrpDProDIle-X_(a), where X_(a) is

[0320] 2-aminoethylamide,

[0321] 5-aminopentylamide, or

[0322] 3-aminopropylamide.

[0323] αAibDTrpDProDVal-X_(b), where X_(b) is

[0324] 2-aminoethylamide,

[0325] dimethylamide, or

[0326] diethylamide.

[0327] αAibDTrpDProDPro-X_(c), where X_(c) is

[0328] 2-aminoethylamide.

[0329] The following compounds are preferred

[0330] αAibDTrpDProDIleXd, where X_(d) is

[0331] 5-aminopentylamide,

[0332] 3-aminopropylamide,

[0333] 2-aminoethylamide, or

[0334] 4-aminobutylamide

[0335] αAibDTrpDProDValX_(e), where X_(e) is

[0336] N-dimethylamide,

[0337] N-diethylamide, or

[0338] 2-aminoethylamide;

[0339] αAibDTrpDProDValX_(f), where X_(f) is

[0340] 5-aminopentylamide;

[0341] αAibDTrpDProDNleX_(g), where X_(g) is

[0342] 5-aminopentylamide;

[0343] αAibDTrpDProDProArgNH₂;

[0344] αAibDTrpDProDValDArgNH₂;

[0345] αAibDTrpDProDValArgNH₂;

[0346] αAibDTrpDProDIleArgNH₂;

[0347] αAibDαNalDProDValArgNH₂;

[0348] αAibDαNalDProDValArgNH₂;

[0349] αAibDαNalDProDIleArgNH₂;

[0350] αAibDαNalDProDValLysNH₂;

[0351] inipDαNalDαNalPheArgNH₂;

[0352] αAibDTrpDProDThrArgNH₂;

[0353] αAibDTrDProDNleArgNH₂;

[0354] αAibDTrpDProDNValArgNH₂;

[0355] αAibDTrpDProDIleArgGlyNH₂;

[0356] αAibDTrpDProDProDIleArgGlyNH₂;

[0357] αAibDTprDProDNleArgGlyNH₂; and

[0358] αAibDTrpDProDThrArgGlyNH₂;

[0359] In one embodiment one uses compound from compounds having theformula

[0360] αAibDTrpDProDProA₄ArgNH₂ or

[0361] αAibDTrpDProDProA₄ArgGlyNH₂.

[0362] Preferred examples are selected from the group consisting of

[0363] αAibDTrpDProDIleArgNH₂

[0364] αAibDTrpDProDIleArgGlyNH₂

[0365] αAibDTrpDProDProDIleArgNH₂, and

[0366] αAibDTrpDProDProDIleArgGlyNH₂.

[0367] In an alternate embodiment, the following peptides are ofinterest:

[0368] DβNaldaTrpDPheLysGlnGlyNH₂

[0369] DAlaDTrpAlaTrpDPheLysValGlyNH₂

[0370] DAlaDβNaLAlaTrpDPheLysGlnGlyGlyGlyNH₂

[0371] DAlaDTrpAlaTrpDPheLysHisGlyNH₂

[0372] These secretagogues can be used therapeutically for any use forwhich growth hormone can be used, such as treating hypothalamicpituitary dwarfism, osteoporosis, burns, and renal failure for acuteuse, for non-union bone fracture, and to promote wound healing.Additionally, it can be used to promote recovery from surgery, andacute/chronic debilitating medical illnesses. Beneficial anaboliceffects result on skin, muscle and bone in relation to the aging processwith a concomitant decrease in body fat. Treatment of cancer patients bythese peptides is also included, for example, prevention and/orreduction of cachexia in cancer patients. These therapeutic uses areaccomplished by using a therapeutically effective amount of thecompound. Such an amount is that needed to promote the release of serumgrowth hormone levels as discussed, infra.

[0373] The compounds of this invention may also be used to enhance bloodGH levels in animals; enhance milk production in cows; enhance bodygrowth in animals such as, e.g., humans, sheep, bovines, and swine, aswell as fish, fowl, other vertebrates and crustaceans; and increase wooland/or fur production in mammals. The amount of body growth is dependentupon the sex and age of the animal species, quantity and identity of thegrowth hormone releasing compound being administered, route ofadministration, and the like.

[0374] Also, the compounds of this invention increase serum GH inhumans; enhance body growth in short stature children; decrease body fatand improve protein metabolism in select children; improve proteinmetabolism of the skin, muscle, bone while decreasing body fat of theelderly, particularly when GH deficiency is present.

[0375] These compounds are also useful for improving serum lipid patternin humans by decreasing in the serum the amount of serum cholesterol andlow density lipoprotein, and increasing in the serum the amount of thehigh density lipoprotein.

[0376] The novel secretagogues of this invention can be synthesizedaccording to the usual methods of solution and solid phase peptidechemistry, or by classical methods known in the art.

[0377] In accordance with another embodiment of the present invention, amethod is provided for promoting release and/or elevation of growthhormone levels in the blood of an animal. This method of promoting therelease and/or elevation of growth hormone levels can also be used totherapeutically treat the aforesaid diseases. Said methods compriseadministering to an animal an effective dose of at least one of theabove-described compounds. In one embodiment, this method is used inanimals other than humans.

[0378] The compounds of this invention can be administered by oral,parenteral (intramuscular (i.m.), intraperitoneal (i.p.), intravenous(i.v.) or subcutaneous (s.c.) injection), nasal, vaginal, rectal orsublingual routes of administration as well as intrapulmonary inhalationcan be formulated in dose forms appropriate for each route ofadministration. Parenteral administration is preferred.

[0379] Solid dose forms for oral administration include capsules,tablets, pills, powders and granules. In such solid dose forms, theactive compound is mixed with at least one inert carrier such assucrose, lactose, or starch. Such dose forms can also comprise, as isnormal practice, additional substances other than inert diluents, e.g.,lubricating agents such as magnesium stearate. In the case of capsules,tablets and pills, the dose forms may also comprise buffering agents.Tablets and pills can additionally be prepared with enteric coatings.

[0380] Liquid dose forms for oral administration include emulsions,solutions, suspensions, syrups, the elixirs containing inert diluentscommonly used in the art, such as water. Besides, such inert diluents,compositions can also include adjuvants, such as wetting agents,emulsifying and suspending agents, and sweetening, flavoring, andperfuming agents.

[0381] Preparations according to this invention for parenteraladministration include sterile aqueous or non-aqueous solutions,suspensions, or emulsions. Examples of non-aqueous solvents or vehiclesare propylene glycol, polyethylene glycol, vegetable oils, such as oliveoil and corn oil, gelatin, and injectable organic esters such as ethyloleate. Such dose forms may also contain adjuvants such as preserving,wetting, emulsifying, and dispersing agents. They may be sterilized by,for example, filtration through a bacteria-retaining filter, byincorporating sterilizing agents into the compositions, by irradiatingthe compositions, or by heating the compositions. They can also bemanufactured in a medicum of sterile water, or some other sterileinjectable medium immediately before use.

[0382] The amount of secretagogues or combination of compounds of thepresent invention administered will vary depending on numerous factors,e.g., the particular animal treated, its age and sex, the desiredtherapeutic affect, the route of administration and which polypeptide orcombination of polypeptides are employed. In all instances, however, adose effective (therapeutically effective amount) to promote release andelevation of growth hormone level in the blood of the recipient animalis used. Ordinarily, this dose level falls in the range of between about0.1 μg to 10 mg of total compound per kg of body weight. The preferredamount can readily be determined empirically by the skilled artisanbased upon the present disclosure.

[0383] For example, in humans when the mode of administration is i.v.the preferred dose level falls in the range of about 01 μg to 10 μg oftotal secretagogue per kg of body weight, more preferably, about 0.5 μgto 5 μg of total secretagogue per kg of body weight, still morepreferably about 0.7 μg about 3.0 μg per kg of body weight. Whencombinations of growth hormone releasing compounds are used, loweramounts of the presently described peptide can be used. For example,combining the presently described secretagogues with, for example, asynergistic compound in Group I of U.S. Pat. No. 4,880,778 such as GHRH,or U.S. Pat. No. 5,663,146 or 5,486,505, a preferred range is about 0.1μg to about 5 μg of the presently described compound per kg of bodyweight and about 0.5 μg to about 15.0 μg of synergistic compound (e.g.GHRH) and more preferably about 0.1 μg to about 3 μg of the presentcompound with about 1.0 μg to about 3.0 μg of the synergistic compoundper kg of body weight.

[0384] When the mode of administration is oral, greater amounts aretypically needed. For example, in humans for oral administration, thedose level is typically about 30 μg to about 1200 μg of compound per kgof body weight, more preferably about 70 μg to about 600 μg of compoundper kg of body weight, still more preferably, about 200 μg to about 600μg of total compound per kg of body weight. Cows and pigs require aboutthe same dose level as humans, while rats typically require higher doselevels. The exact level can readily be determined empirically based uponthe present disclosure.

[0385] In general, as aforesaid, the administration of combinations ofgrowth hormone releasing peptides will allow for lower doses of theindividual growth hormone releasing compounds to be employed relative tothe dose levels required for individual growth hormone releasingcompounds in order to obtain a similar response, due to the synergisticeffect of the combination.

[0386] Also included within the scope of the present invention arecompositions that comprise, as an active ingredient, the organic andinorganic addition salts of the above-described polypeptides andcombinations thereof; optionally, in association with a carrier,diluent, slow release matrix, or coating.

[0387] The organic or inorganic addition salts of the growth hormonereleasing compounds and combinations thereof contemplated to be withinthe scope of the present invention include salts of such organicmoieties as acetate, trifluoroacetate, oxalate, valerate, oleate,laurate, benzoate, lactate, tosylate, citrate, maleate, fumarate,succinate, tartrate, naphthalate, and the like; and such inorganicmoieties as Group I (i.e., alkali metal salts), Group II (i.e. alkalineearth metal salts) ammonium and protamine salts, zinc, iron, and thelike with counterions such as chloride, bromide, sulfate, phosphate andthe like, as well as the organic moieties referred to above.

[0388] Pharmaceutically acceptable salts are preferred whenadministration to human subjects is contemplated. Such salts include thenon-toxic alkali metal, alkaline earth metal and ammonium salts commonlyused in the pharmaceutical industry including sodium, potassium,lithium, calcium, magnesium, barium, ammonium and protamine salts whichare prepared by methods well known in the art. The term also includesnon-toxic acid addition salts which are generally prepared by reactingthe compounds of this invention with a suitable organic or inorganicacid. Representative salts include hydrochloride, hydrobromide, sulfate,bisulfate, acetate, oxalate, valerate, oleate, laurate, borate,benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate,succinate, tartrate, napthylate and the like.

[0389] The invention will be further illustrated by the followingnon-limiting examples.

EXAMPLES OF THE INVENTION

[0390] The following examples are designed to illustrate certain aspectsof the present invention. The examples are not intended to becomprehensive of all features and all embodiments of the presentinvention, and should not be construed as limiting the claims presentedherein. General Methods for Synthesis

[0391] 1H NMR spectra were measured (SiMe₄ internal standard) on aGE-500 (500 MHz) Spectrometer. Mass spectra data were obtained by usinga “Lasermat” Laser Desorption Mass Spectrometry. Reagents were obtainedfrom commercial sources and used without further purification. Solventswere dried according to standard procedures. Scheme 1 can be utilizedfor additions with any amine group recorded in Table 1.

Example 1 Synthesis of the Growth Hormone Releasing Peptides

[0392] Paramethyl benzhydrylamine hydrochloride (pMe-BHA HCl) resin isplaced in a reaction vessel on a commercially available automatedpeptide synthesizer. The resin is substituted with free amine up to aloading of about 5 mmoles per gram. The compounds are prepared bycoupling individual amino acids starting at the carboxy terminus of thepeptide sequence using an appropriate activating agent, such as N,N′dicyclohexylcarbodiimide (DCC). The alpha amine of individual aminoacids are protected, for example, as the t-butyloxycarbonyl derivative(t-Boc) and the reactive side chain functionalities are protected asoutlined in Table 1. TABLE 1 Side Chain Protecting Groups Suitable forSolid Phase Peptide Synthesis Arginine N_(g) -Tosyl Aspartic AcidO-Benzyl Cysteine S-para-Methylbenzyl Glutamic Acid O-Benzyl HistidineN^(im)-Tosyl Lysine N^(ε)-2,4-Dichlorobenzyloxycarbonyl MethionineS-Sulfoxide Serine O-Benzyl Threonine O-Benzyl Tryptophan N^(in)-FormylTyrosine O-2,6-Dichlorobenzyl

[0393] Prior to incorporation of the initial amino acid, the resin isagitated three times (about one minute each) with dichloromethane(CH₂C₁₂: about 10 ml/gm of resin), neutralized with three agitations(about two minutes each) of N,N-diisopropylethylamine (DIEA) indichloromethane (10:90; about 10 ml/gm of resin) and agitated threetimes (about one minute each) with dichloromethane (about 10 mL/gm ofresin). The initial and each of the subsequent amino acids are coupledto the resin using a preformed symmetrical anhydride using about 6.0times the total amount of the reaction capacity of the resin of asuitably protected amino acid and about 2.0 times the total amount ofthe binding capacity of the resin of DIC in an appropriate amount ofdichloromethane. For amino acids with a low dichloromethane solubility,N,N-dimethylformamide (DMF) is added to achieve a homogenous solution.Generally, the symmetrical anhydride is prepared up to 30 minutes priorto introduction into the reaction vessel at room temperature or below.The dicyclohexylurea that forms upon preparation of the symmetricalanhydride is removed via gravity filtration of the solution into thereaction vessel. Progress of the coupling of the amino acid to the resinis commonly monitored via a color test using a reagent such as ninhydrin(which reacts with primary and secondary amines). Upon complete couplingof the protected amino acid to the resin (>99%), the alpha amineprotecting group is removed by treatment with acidic reagent(s). Acommonly used reagent consists of a solution of trifluororacetic acid(TFA) in dichloromethane (33:66).

[0394] After the desired amino acid sequence has been completed, thedesired peptide can be cleaved from the resin support by treatment witha reagent such as hydrogen fluoride (HF) which not only cleaves thepeptide from the resin, but also cleaves most commonly used side-chainprotecting groups. When the BHA or p-Me-BHA resin is used, HF treatmentresults directly in free peptide amides. When an amino acid-Merrifieldresin is used, free peptide alkylamides are cleaved by treatment with anappropriate amine (in this case, use of Boc-N^(ε)-FMOC-Lys would allowsimultaneous removal of the FMOC group).

[0395] The complete procedure for incorporation of each individual aminoacid residue onto the resin is outlined in Table 2. TABLE 2 Procedurefor Incorporation of Individual Amino Acids onto a Resin ReagentAgitations Time/Agitation 1. Dichloromethane 3 1 min. 2.TFA-Dichloromethane 1 2 min. (33:66) 3. TFA-Dichloromethane 1 20 min.(33:66) 4. Dichloromethane 3 1 min. 5. DIEA, DMF 2 2 min. (10:90) 6.Dichloromethane 3 1 min. 7. Boc amino acid/DIC 1 15-120 min* 8.Dichloromethane 3 1 min. 10. Monitor progress of the coupling reaction**11. Repeat steps 1-12 for each individual amino acid

[0396] Using this procedure the compounds described in Tables 3, 4 and 5were made.

Example 2 In Vivo GH Release in Rats

[0397] Immature female Sprague-Dawley rats were obtained from theCharles River Laboratories (Wilmington, Mass.). After arrival they werehoused at 25° C. with a 14:10 hour light:dark cycle. Water and Purinarat chow were available ad libitum. Pups were kept with their mothersuntil 21 days of age.

[0398] Twenty-six day old rats, six rats per treatment group, wereanesthetized interperitoneally with 50 mg/kg of pentobarbital 20 minutesprior to i.v. treatment with peptide. Normal saline with 0.1% gelatinwas the vehicle for intravenous (i.v.) injections of the peptides. Theanesthetized rats, weighing 55-65 grams, were injected i.v. with thequantity of grown hormone releasing compounds indicated in Table 3.Injection was made as a 0.1 mL solution into the jugular vein.

[0399] All animals were sacrificed by guillotine 10 minutes after finaltest injection (see Table 3). Trunk blood for the determination of bloodGH levels was collected following decapitation. After allowing the bloodto clot, it was centrifuged and the serum was separated from the clot.Serum was kept frozen until the day of sampling for radioimmunoassay(RIA) determination of growth hormone levels according to the followingprocedure, as developed by the National Institute of Arthritis, Diabetesand Digestive and Kidney Diseases (NIADDK).

[0400] Reagents are generally added to the RIA analysis tubes at asingle sitting, at refrigerator temperature (about 4° C.) in thefollowing sequence:

[0401] (a) buffer,

[0402] (b) “cold” (i.e., non-radioactive) standard or unknown serumsample to be analyzed,

[0403] (c) radio-iodinated growth hormone antigen, and

[0404] (d) growth hormone antiserum.

[0405] Reagent addition is generally carried out so that there isachieved a final RIA tube dilution of about 1:30,000 (antiserum to totalliquid volume; vol:vol).

[0406] The mixed reagents are then typically incubated at roomtemperature (about 25° C.) for about 24 hours prior to addition of asecond antibody (e.g., goat or rabbit anti-monkey gamma globulin serum)which binds to and causes precipitation of the complexed growth hormoneantiserum. Precipitated contents of the RIA tubes are then analyzed forthe number of counts in a specified period of time in a gammascintillation counter. A standard curve is prepared by plotting numberof radioactive counts versus growth hormone (GH) level. GH levels ofunknown are then determined by reference to the standard curve.

[0407] Serum GH was measured by RIA with reagents provided by theNational Hormone and Pituitary Program.

[0408] Serum levels in Tables 3 and 4 are recorded in ng/mL in terms ofthe rat GH standard of 0.61 International Units/mg (IU/mg). Data isrecorded as the mean ±standard error of the mean (SEM). Statisticalanalysis was performed with Student's t-test. In Table 3, the resultsshown are the average of studies with six rats.

Example 3 Synthesis of Aib-DTrp-DPro-diisobutylamide (YL-156)

[0409] (1) Synthesis of DPro-Diisobutylamide (1):

[0410] 1 mmol of Boc-DPro (Boc=tert-Butoxycarbonyl group) was dissolvedin 30 ml dry CH₂Cl₂ in a 100 ml round bottom flask, with 1 mmol of1-hydroxybenzotriazole added while stirring under N₂ atmosphere in anice-bath, then 1.05 mmol of 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide HCl was added in 10 ml dry CH₂Cl₂ at a fast drop rate andthe reaction mixture was stirred for 1 hour at 0° C. 1.1 mmol ofdiisobutylamine in 10 ml of CH₂Cl₂ was added dropwise and stirring wascontinued for a further 18 h at ambient temperature. The reactionmixture was washed with 20 ml of 20% aqueous citric acid, 20 ml ofsaturated aqueous NaHCO₃, and 20 ml of saturated aqueous sodiumchloride. The organic layer was separated and dried over anhydrousmagnesium sulfate, filtered and concentrated in vacuum. Furtherpurification was done by flash column chromatography (SiO₂, CHCl₃/MeOH,95:5) to afford white solid of Boc-DPro-diisobutylamide.

[0411] Under N₂ atmosphere, the Boc-DPro-diisobutylamide was dissolvedin 25 ml of CH₂Cl₂ and 1-ml of trifluoracetic acid was added while beingstirred. The reaction mixture was stirred for 30 min. Volatiles wereremoved under vacuum and the residue was dissolved in 30 ml of CH₂Cl₂and washed with 10 ml saturated NaHCO₃ aqueous solution. The organiclayer was removed and the aqueous layer was extracted with CH₂Cl₂ (3×10ml). The organic layer was dried over anhydrous sodium sulfate andfiltered and the solvent was removed in vacuum. The residue was furtherpurified by column chromatography (SiO₂, CHCl₃/MeOH, 85:15) to afford0.73 mmol (73%) of compound (1) which was characterized by TLC on massspectra, M⁺=225.1.

[0412] (2) Synthesis of DTrp-DPro-diisobutylamide (2):

[0413] In a 100 ml round bottom flask, 0.70 mmol of Boc-DTrp wasdissolved in ml dry CH₂Cl₂ and 0.70 mmol of 1-hydroxybenzotriazole wasadded while stirring under N₂ atmosphere in an ice-bath then 0.75 mmolof 1-ethyl-3-(3′-dimethylaminopropyl) carbodiimide HCl was added in 15ml dry CH₂Cl₂ at a fast drop rate and the reaction mixture stirred for 1hour at 0° C. 0.71 mmol of (1) in 20 ml of CH₂Cl₂ was added dropwise andstirring was continued for a further 18 h at ambient temperature. Thereaction mixture was washed with 20 ml of 20% citric acid aqueoussolution, 20 ml of saturated NaHCO₃ aqueous solution, and 20 ml ofsaturated sodium chloride aqueous solution. The organic layer wasseparated and dried over anhydrous magnesium sulfate, filters andconcentrated by vacuum. Further purification was done by flash columnchromatography (CHCl₃/MeOH, 95:5) to afford white solid ofBoc-DTrp-D-diisobutylamide.

[0414] Under N₂ atmosphere, the Boc-DTrp-DPro-diisobutylamide wasdissolved in 25 ml of CH₂Cl₂, 1 ml of methylsulfide and 0.5 ml of1,2-ethanedithiol was added as scavenger in suppressing the indolealkylation of tryptophane. 10 ml of trifluoracetic acid was addeddropwise while being stirred. The reaction mixture was stirred for 30min. Volatiles were removed under vacuum and the residue was dissolvedin 30 ml of CH₂Cl₂ and washed with 10 ml saturated NaHCO₃ aqueoussolution. The organic layer was dried over anhydrous sodium sulfate andfiltered and the solvents were removed in vacuum. The residue wasfurther purified by column chromatography (SiO₂, CHCl₂/MeOH, 85:15) toafford 0.55 mmol (78.5%) of compound (2) which was characterized by TLCand mass spectra, M⁺=411.5.

[0415] (3) Synthesis of Aib-DTrp-DPro-diisobutylamide (YL-156):

[0416] In a 100 ml round bottom flask, 0.50 mmol of Boc-Aib(Aib=α-aminoisobutyric acid) was dissolved in 30 ml dry CH₂Cl₂ and then0.51 mmol of 1-hydroxybenzotrizole was added while stirring under N₂atmosphere in an ice-bath, 0.55 mmol of1-ethyl-3-(3′-dimethylaminopropyl) carbodiimide HCl was added in 20 mldry CH₂Cl₂ at a fast drop rate and the reaction was stirred for 1 hourat 0° C. 0.51 mmol of (2) in 15 ml of CH₂Cl₂ was added dropwise andstirring was continued for a further 18 h at ambient temperature. Thereaction mixture was washed with 20 ml of 20% citric acid aqueoussolution, 20 ml of saturated NaCHO₃ aqueous solution, and 20 ml ofsaturated sodium chloride aqueous solution. The organic layer wasseparated and dried over anhydrous magnesium sulfate, filtered andconcentrated in vacuum. Further purification was done by flash columnchromatography (CHCl₃/MeOH, 95:5) to afford white solid ofBoc-Aib-DTrp-DPro-diisobutylamide.

[0417] Under N₂ atmosphere, the Boc-Aib-DTrp-DPro-diisobutylamide wasdissolved in 30 ml of CH₂Cl₂, 1 ml of methylsulfide and 0.5 ml of1,2-ethanedithiol were added as scavengers to suppress the indolealkylation of tryptophan. 10 ml of trifluoracetic acid was addeddropwise while being stirred. The reaction mixture was stirred for 30min. Volatiles were removed under vacuum and the residue was dissolvedin 30 ml of CH₂Cl₂ and washed with 10 ml saturated NaHCO₃ aqueoussolution. The organic layer was removed and the aqueous layer wasextracted with CH₂Cl₂ (3×10 ml). The organic layer was dried overanhydrous sodium sulfate, and filtered and the solvents were removed invacuum. The residue was further purified by column chromatography (SiO₂,CHCl/MeOH, 85:15) to afford 0.43 mmol (86.2%) of compound (YL-156) whichwas characterized by TLC and mass spectra M⁺=497.6.

Example 4 Synthesis of inip-DαNal-DTrp-Phe-2-aminoethylamide YL-105)

[0418] 3.5 g of Wang resin with the peptide attached was supplied byResearch Genetics Laboratory. It was added to a 100 ml round-bottomflask and then sequentially 40 ml of dry CH₂Cl₂, 4 ml of methanol and 2ml of 1,2-diaminoethane were added while stirring under N₂ atmosphere.The reaction mixture was stirred for 72 hours at RT. The reactionmixture was filtered and the resin was washed with 20 ml of dry CH₂Cl₂,20 ml of methanol. The solid resin was discarded. The organic solventwas removed by vacuum. The solid residue was further purified by flashcolumn chromatography (SiO₂, CHCl₃/MeOH, 95:5) to afford white solid ofYL-105.

[0419] Further purification was performed by preparative HPLC. Molecularweight was determined by MS.

Example 5 Synthesis of (N-2-hydroxylethyl-Aib-DTrp-DPro-diisobutylamide(YL-185) (Reductive Alkylation)

[0420] 1 mmol of YL-156 (αAibDTrpDPro-diisobutylamide) was dissolved in40 ml dry methanol in a 100 ml round-bottom flask and 1.5 mmol of NaBH₄in THF was added while stirring under N₂ atmosphere. The solution wasacidified by adding trifluoracetic acid in methanol to adjust the pH to6.5. Then 1.15 mmol of ethylaldehyde was added in 10 ml dry methanol andthe reaction mixture was stirred for 16 hours at RT. The solvent wasremoved by vacuum. The remaining residue was dissolved in 30 ml CH₂Cl₂and washed with 20 ml of saturated aqueous NaHCO₃. The organic layer wasseparated and dried over anhydrous magnesium sulfate, filtered, andconcentrated in vacuum. Further purification was done by flash columnchromatography (SiO₂, CHCl₃/MeOH, 95:5) to afford white solid of YL-185.

[0421] Further purification was performed by preparative HPLC. Themolecular weight was determined by MS.

Example 6 Synthesis of (N-isobutyl)Aib-DTrp-DPro-diisobutylamide(YL-194) (Hoffman Alkylation)

[0422] 1 mmol of YL-156 (αAibDTrpDPro-diisobutylamide) was dissolved in40 ml dry CH₂Cl₂ in a 100 ml round-bottom flask. 2 mmol of K₂CO₃ wasthen added while stirring under N₂ atmosphere. 1.15 mmol of1-bromo-2-methylpropane was added in 10 ml dry CH₂Cl₂ and the reactionmixture stirred for 72 hours at RT. The reaction mixture was washed with20 ml of saturated aqueous NaHCO₃ and 20 ml of saturated aqueous sodiumchloride. The organic layer was separated and dried over anhydrousmagnesium sulfate, filtered and concentrated under vacuum. Furtherpurification was done by flash column chromatography (SiO₂, CHCl₃/MeOH,95:5) to afford white solid of YL-194.

[0423] Further purification was performed by preparative HPLC. Molecularweight was determined by MS.

Example 7 Synthesis of Aib-DTrp-DTrp-Phe-Arg-5-aminopentylamide CL-174)

[0424] 0.7 mmol of Fmoc-Aib-DTrp-DTrp-Phe-ArgCOOH was synthesized byResearch Genetics Laboratory by the solid phase method and added to a100 ml round-bottom flask with 40 ml of dry CH₂Cl₂. 0.70 mmol of1-hydroxybenzotriazole was added while stirring under N₂ atmosphere inan ice-bath and subsequently 0.75 mmol of1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide HCl was added in 15 mldry CH₂Cl₂ at a fast drop rate. The reaction mixture was stirred for 1hour at 0° C. 10 mmol of 1,5-diaminopentane in 20 ml of CH₂Cl₂ was addedquickly and stirring was continued for an additional 18 h at ambienttemperature. The reaction mixture was washed with 20 ml of saturatedNaHCO₃ aqueous solution and 10 ml of saturated sodium chloride aqueoussolution. The organic layer was separated and dried over anhydrousmagnesium sulfate, filtered and concentrated under vacuum. Furtherpurification was done by flash column chromatography (CHCl₃/MeOH, 95:5)to afford white solid of Fmoc-Aib-DTrp-DTrp-Phen-ArgCONH(CH₂)₅NH₂. Thiscompound was dissolved in 20 ml of CH₂Cl₂ and under N₂ atmosphere 10 mlof piperidine was added. The solution was stirred for another 4 hours.The solvent was removed by vacuum and the residue was further purifiedby flash column chromatography (CHCl₃/MeOH, 95:5) to afford white solidof YL-174.

[0425] Further purification was performed by preparative HPLC. Molecularweight was determined by MS.

Example 8 Synthesis of Aib-DTrp-DPro-3-methylpiperidinamide (YL-111)

[0426] (Aib-DTrp-DPro-R, R=various of amine end groups, for examplepiperidine, 3-methyl piperidine, etc. All other Aib-DTrp-DPro-Rcompounds can be synthesized by using the same procedure):

[0427] (1) Synthesis of DPro-3-methylpiperidinamide (methylpiperidine)(1):

[0428] 1 mmol of Boc-DPro (Boc=tert-Butoxycarbonyl group) was dissolvedin 30 ml dry CH₂Cl₂ in a 100 ml round-bottom flask, 1 mmol of1-hydroxybenzotriozole added while stirring under N₂ atmosphere in anice-bath, 1.05 mmol of 1-ethyl-3-(3′-dimethylaminopropyl) carbodimideHCL was added in 10 ml dry CH₂Cl₂ at a fast drop rate and the reactionmixture stirred for 1 hour at 0° C. 1.1 mmol of 3-methylpiperazine in 10ml of CH₂Cl₂ was added dropwise and stirring was continued for anadditional 18 h at ambient temperature. The reaction mixture was washedwith 30 ml of 20% aqueous citric acid, 30 ml of saturated aqueousNaHCO₃, and 30 ml of saturated aqueous sodium chloride. The organiclayer was separated and dried over anhydrous magnesium sulfate,filtered, and concentrated in vacuum. Further purification was done byflash column chromatography (SiO₂, CHCl₃/MeOH, 95:5) to afford whitesolid of Boc-DPro-D-piperidinamide.

[0429] Under N₂ atmosphere, the Boc-DPro-3-piperidinamide was dissolvedin ml of CH₂Cl₂ and 10 ml of trifluoracetic acid added while stirring.The reaction mixture was stirred for 30 min. All volatiles were removedunder vacuum and the residue dissolved in 30 ml of CH₂Cl₂ and washedwith 10 ml saturated NaHCO₃ aqueous solution. The organic layer wasremoved and the aqueous layer extracted with CH₂Cl₂ (3×10 ml). Theorganic layer was dried over anhydrous sodium sulfate and filtered andthe solvent was removed by vacuum. The residue was further purified bycolumn chromatography (SiO₂, CHCl₃/MeOH, 85:15) to afford 0.65 mmol(65%) of compound (1) which was characterized by TLC and mass spectra,M⁺=196.3.

[0430] (2) Synthesis of DTrp-DPro-3-methylpiperidinamide(methylpiperidine) (2):

[0431] In a 100 ml round-bottom flask, 0.63 mmol of Boc-DTrp wasdissolved in ml dry CH₂Cl₂ 0.66 mmol of 1-hydroxybenzotrizole was addedwhile stirring under N2 atmosphere in an ice-bath. 0.63 mmol of1-ethyl-3-(3′-dimethylaminopropyl) carbodiimide HCL was added in 10 mldry CH₂Cl₂ at a fast drop rate and the reaction mixture was washed with20 ml of 20% citric acid aqueous solution, 20 ml of saturated NaHCO₃aqueous solution and 20 ml of saturated sodium chloride aqueoussolution. The organic layer was separated and dried over anhydrousmagnesium sulfate, filtered and concentrated in vacuum. Furtherpurification was done by flash column chromatography (CHCl₃/MeOH, 95:5)to afford white solid of Boc-DTrp-DPro-3-piperidinamide.

[0432] Under N₂ atmosphere, the Boc-DTrp-DPro-3-piperidinamide wasdissolved in 25 ml of CH₂Cl₂ and 10 ml of trifluoracetic was added whilebeing stirred. The reaction mixture was stirred for 30 min. Allvolatiles were removed under vacuum and the residue was dissolved in 30ml of CH₂Cl₂ and washed with 10 ml saturated NaHCO₃ aqueous solution.The organic layer was removed and the aqueous layer was extracted withCH₂Cl₂ (3×10 ml). The organic layer was dried over anhydrous sodiumsulfate, filtered and the solvent removed in vacuum. The residue wasfurther purified by column chromatography (SiO₂, CHCl₃/MeOH, 85:15) toafford 0.43 mmol (68.3%) of compound (2) which was characterized by TLCand mass spectra, M,=382.46.

[0433] (3) Synthesis of Aib-DTrp-DPro-3-methylpiperidinamide(methylpiperidine) CL-111):

[0434] In a 50 ml round bottom flask, 0.33 mmol of Boc-Aib was dissolvedin 20 ml dry CH₂Cl₂ and then 0.31 mmol of 1-hydroxybenzotriazole wasadded while stirring under N₂ atmosphere in an ice-bath. 0.35 mmol of1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide HCL was added in 10 mldry CH₂Cl₂ at a fast drop rate and the reaction mixture was stirred for1 hour at 0° C. 0.30 mmol of (2) in 15 ml of CH₂Cl₂ was added dropwiseand stirring was continued for an additional 18 h at ambienttemperature. The reaction mixture was washed with ml of 20% citric acidaqueous solution, 20 ml of saturated NaHCO₃ aqueous solution and 20 mlof saturated sodium chloride aqueous solution. The organic layer wasseparated and dried over anhydrous magnesium sulfate, filtered andconcentrated in vacuum. Further purification was done by flash columnchromatography (CHCl₃/MeOH, 95:5) to afford white solid ofBoc-Aib-DTrp-DPro-3-piperidinamide.

[0435] Under N₂ atmosphere, the Boc-Aib-DTrp-DPro-3-piperidinamide wasdissolved in 25 ml of CH₂Cl₂ and 10 ml of trifluoracetic acid was addedwhile being stirred. The reaction mixture was stirred for 30 min. Alvolatiles were removed under vacuum and the residue was dissolved in 30ml of CH₂Cl₂ and washed with 10 ml saturated NaCHO₃ aqueous solution.The organic layer was removed and the aqueous layer was extracted withCH₂Cl₂ (3×10 ml). The organic layer was dried over anhydrous sodiumsulfate, filtered and the solvent removed in vacuum. The residue wasfurther purified by column chromatography (SiO₂, CHCl₃/MeOH, 85:15) toafford 0.28 mmol (84.8%) of compound (YL-111) which was characterized byTLC and mass spectra M⁺=468.6.

Biological Activity

[0436] In vitro and in vivo activity of certain compounds weredetermined in rats and adult beagle dogs (in vivo activity only). Theresults are described in Tables 3, 4, 5, 6 and 7 below.

[0437] The GHRP-2 (reference standard) has the structureDAla-DβNal-Ala-Trp-DPhe-Lys-NH₂ (Chen and Clarke, J. Neuroend. 7: 179(1995)). TABLE 3 In Vitro Release of Growth Hormone in Rat Compound GHR¹-N-Aib ng/ DTrpX* GHRP-2 Where X is: control .001 .0001 .0003 .001.003 .01 .03 .1 .3 1 DPro NH₂ 752 1525 922 1102 997 1250 1535 1550 1716DPro-diiso- 523 1307 1322 1529 1427 1155 1124 butylamide R¹-N-2- 3411427 — — 452 326 526 820 1163 1217 Ohethyl DPro-diiso- butylamideR¹-N₂N-di-2- 341 1427 — — 433 395 446 592 905 1206 OHethyl/ DPro diiso-butylamide R¹-N- 510 1413 — — 523 461 779 742 1079 1292 ethyl/DProdiisobutyl- amide R¹-Nentyl/ 341 1427 — — 570 698 982 1307 1467 1387DPro diisobutyl- amide DPro- 543 1065 554 578 554 630 823 908 925dipropyl- amide DPro- 523 1307 512 647 833 995 1253 1612 butylamideDPro- 622 1290 569 830 1172 1184 1335 1451 pentylamide DPro- 523 13071348 1561 1287 1021 1451 dipentyl- amide DPro- 389 821 529 553 721 728886 978 piperidine-3- methylbenzyl ether N,N- 397 593 418 395 489 536642 diethylnipe- cotamide -N-piperazine 553 1167 672 675 856 1049methyl- sulfonamide DPro- 389 821 375 368 481 587 802 912 diethylamideDPro-m- 308 1052 434 458 633 837 968 methylpiper- idine DPro-3,3- 4661126 926 1118 1169 1177 1283 diphenyl- propylamide DPro-4- 376 1125 419451 540 808 piperidino- piperidin- amide DPro-4- 455 1520 624 777 10341186 1533 1772 phenylpiper- idinamide DPro-N- 389 821 467 532 573 605816 909 methyl- piperiazine DPro-2- 397 593 394 413 433 485 548morpholino- ethylamine DPro- 385 915 440 512 691 819 956 922 1057spiroindole methyl- sulfonamide DPro- 614 1288 714 873 1149 1241pyrrolidine amide DPro- 486 1344 836 1127 1283 1235 1258 1220 1327indoline amide DPro-3- 486 1344 1008 1199 1209 1348 1626 1567 piperidinemethanol amide DPro-tropin 510 1220 542 797 1001 1124 1234 amideDTrpPhe- 752 1525 1228 1416 1712 1648 1621 Arg-5-amino pentamide

[0438] TABLE 4 In Vivo Release of Growth Hormone in Rat CompoundR¹-N₂-AibDrpX* GHRP-2 GH ng/ml Where X is: control .1 .1 .3 1 3 10 30100 DPro NH₂ 223 1580 326 433 1159 2217 3155 DPro- 111 1066 642 15241837 2307 2913 diisobutylamide R¹-N-2-OHethyl/ 92 2051 — — — 156 259 451— DPro-diiso- butylamide R¹N,N-di-2- 96 799 — — — 124 208 543 OHethyl/DPro-diiso- butylamide R¹N-ethyl/ 92 2051 — — 189 177 268 374 —DPro-diiso- butylamide R¹-N-pentyl/ 92 2051 — — 124 398 371 789 —DPro-diiso- butylamide DPro-dipropylamide 91 1082 92 220 305 579 16462089 DPro-butylamide 111 1066 196 329 647 2005 1596 DPro-pentylamide 1701289 310 581 820 1660 2280 DPro-dipentylamide 128 1071 87 182 322 355632 482 1206 DPro-piperidine-3- 150 1235 669 1725 2319 methyl-benzylether N,N-diethylnipecot- 117 579 221 928 2070 2896 2186 amide-N-piperazine 113 942 241 933 1965 1997 methyl-sulfonamideDPro-diethylamide 128 919 448 766 1719 2465 3088 DPro-m- 93 445 832 15571570 1762 methylpiperidine DPro-3,3-diphenyl- 114 1106 141 147 138 249383 624 propylamide DPro-4-piperidino- 150 1235 378 1318 2403piperidin-amide DPro-4- 111 568 112 238 499 phenylpiperidin- amideDPro-N-methyl- 128 919 218 425 1974 2314 piperazine DPro-2-morpholino-111 568 900 1585 2195 ethylamine DPro-spirouidole 120 586 192 485 8611177 metbyl-sulfonamide DPro-pyrrolidine 98 1227 1024 2116 2381 amideDPro-indoline amide 69 1279 142 317 269 885 DPro-3-piperidine 91 1082155 668 1483 2616 2711 methanol amide DPro-tropin amide 73 1814 114 87183 362 383 769 DTrpPhe-Arg-5- 109 1718 262 274 2272 2929 aminopentamide 8 0

[0439] TABLE 5 In Vivo Release of Growth Hormone in Adult Beagle DogsCompound oral Time R¹-N₂-AibDTrpX* dose (hr) Where X is: (mg/kg) 0 0.5 12 3 4 5 6 7 8 DPro NH₂ 4 0.7 38 14 9 5 13 7.1 3.3 4 2.5 1.3 4 0.8 54 3015 12 4.8 4.2 3.4 1 0 8 DPo- 4 0.8 27 9.4 14 22 22 21 11 6.9 5.4diisobutylamide 4 1.4 141 50 74 15 7.5 4 4.4 5 7 2.3 2 0 6 54 30 22 15 74.6 4.8 2 7 1.8 1 2.6 85 30 16 7.7 6 0.9 2.5 2.5 1 6 1 <0.5 128 50 24 245.6 6.1 2.9 2.2 — 1 1.5 89 59 30 11 7 6.2 5.2 3.7 3.2 R¹-N-2-OHethyl/ 13.8 102 26 25 10 6.1 5.6 4.0 5.2 5.0 DPro-diisobutyl- 1 1 62 30 19 5 63.8 2.0 2.5 2.0 1.6 amide 1 R¹-N₂N-di-2- 1 OHethyl/DPro- diisobutylamideR¹-N-ethyl/ 4 1.3 100 29 20 9.4 3.9 2.2 2.4 1.5 5.6 DPro-diisobutyl- 1 11 17 4.4 1 2 1.5 1.4 1.1 1.2 1 4 1.2 amide R¹-N-pentyl/ 1DPro-diisobutyl- amide DPro-dipropylamide 4 3.2 112 52 29 25 13 6.1 3.62.9 2.5 1 0.6 27 19 5 6 1.6 1.6 0.6 1.4 0.8 0.8 DPro-butylamide 4 1.1 9243 26 53 14 5.4 3.5 3.9 1.3 2 1.8 60 40 13 3.8 3.7 2.2 2.6 2.4 1.7DPro-pentylamide 4 1 72 12 11 6 4.9 3.5 2.5 1.9 1.4 DPro-dipentylamide 42.3 53 20 1.3 15 15 8.9 9.2 6.6 4 3 4 3.7 32 11 8.4 7.2 3.6 3.5 2.3 2.7<0.1 4 2.9 11 11 15 3 3.3 2.5 2.7 2.3 2 DPro-piperidine-3- 4 2 >12 59 6328 11 6.7 4.2 4.1 1.8 methyl-benzyl ether 4 0.8 8 28 27 11 14 14 11 4.76.8 2 3.2 127 42 63 45 13 5.5 4.5 3.4 3.2 2 3.6 169 39 23 6.3 4.5 1.72.7 2.3 1.9 F0.5iv 2.9 112 78 27 9.3 4.5 4.1 2.9 4.1 4.1 81N,N-diethylnipe- 4 1.7 57 13 5 3 5 5 3.4 3.1 1.9 2 1.7 cotamide 4 0.9 438 2 2 1 0.8 0 9 2.1 6 9 0.9 4F 2.7 6 3 7 3 3.7 2 2 0.9 10 3 6 3 5 3.5 35 1 -N-piperazine 4 2 1 57 12. 8.7 3.8 1.7 2.2 1.6 6.3 3.2methyl-sulfonamide 5 DPro-diethylamide 4 2.4 56 38 29 28 16 9.1 6.2 3.92 8 4 1.7 134 89 105 86 16 7.1 5.1 4.5 3 2 F0 5iv 1 6 60 18 6 3 7 2.5 21.9 1.7 2.5 DPro-m- 4 1 54 — 50 52 20 27 8 1 9 6 1.7 methylpiperidine 4F1.4 72 84 18 4.7 3.5 1.4 1 1 1 6 1 5 4 2.1 118 55 54 53 34 13 11 11 6.42 1 2 128 59 29 12 8.9 3 6 3 3 1 7 1 1 6 53 19 15 9.6 3.1 2.2 1 5 2.2 11 2 63 32 17 13 12 1.5 2.4 3 2 2 DPro-3,3-diphenyl- 4 1.6 119 54 17 1610 5.6 4.2 3.3 2.7 propylamide 4 2.2 54 12 8.6 7 4 13 5.9 3.4 3 nsDPro-N-methyl-1- 4 1 100 22 83 7.9 4 8 2 6 2 9 2.3 1.8 piperazine 0.5iv0.8 41 31 7 3.3 2 6 1 5 2.4 0.9 1.1 DPro-spiroundole 4 1.5 <0. 5.5 1.61.5 2 2 4.7 1.7 1.6 0.9 methyl-sulfonamide 5 DPro-pyrrolidine 4 2 3 10428 18 7.1 5.1 3 2 2.7 2.2 2.3 amide 4 2.1 63 32 45 30 11 6 4.9 4 1 3.6DPro-indole amide 4 1.2 7 7.5 5.8 4.7 3.1 2.8 2.5 2 1.6DPro-3-piperidine 4 2.3 55 14 7.5 2.9 3.8 3.4 2 4 2.3 1.8 methanol amideDPro-tropinamide 4 1.9 72 47 5.5 3.8 3.8 2.8 2.5 2.2 2.2 DTrpPhe-Arg-5-2 3.1 83 20 6.8 3.9 2.9 3.3 3.1 3.3 3 amino pentamide 1 2.5 38 8.5 2.82.3 1.4 1.7 2.1 2 0.8

[0440] TABLE 6 In Vivo * Release of GH Rat GHRP-2 GH ng/ml # Compound ivcontrol .1 .01 .03 .1 .3 1 3 10 30 861 inipDαNalDTrpNH₂ 145 1251 4852197 2380 1473 inipDαNalDValNH₂ 145 1251 225 225 1466 αAibDTrpDValNH₂145 1251 124 418 1415 αAibDTrpDProDSerNH₂ 120 1465 820 1658 2306 28961417 αAibDTrpDProDArgNH₂ 120 1465 1362 2161 2057 1246αAibDTrpDProDPheNH₂ 92 566 203 594 1901 2339 1248 αAibDTrpDProDTrpNH₂145 1343 229 1814 1460 αAibDTrpDValDValNH₂ 145 1343 104 240 1461αAibDValDProDValNH₂ 145 1343 160 261 1464 αAibDValDValDValNH₂ 145 134396 197 1468 αAibDTrpDProDLysNH₂ 145 1343 157 791 1462αAibDProDProDValNH₂ 145 1251 218 185 1472 inipDαNalDTrpDValNH₂ 145 1251174 142 154 1019 1489 αAibDTrpDProIleNH₂ 135 1734 445 355 1884 1476αγAbuDαNalDTrpDIleNH₂ 166 1175 97 111 152 152 1495inipDαNalDTrpDProIleNH₂ 166 1175 824 1971 1496 inipDαNalDTrpPheIleNH₂166 1175 1638 2055 1471 inipDαNalDTrpDValArgNH₂ 145 1251 98 184 843 1469αAibDTrpDProDValDValNH₂ 164 411 783 2450 1975 1480αAibDTrpDProDProDPalNH₂ 78 990 245 622 2775 1481αAibDTrpDProDValArgDProNH₂ 164 411 1703 2145 2278 2511 1484αAibDTrpDProDIleDArgNH₂ 105 750 317 562 1863 2224 2446 1475αγAbuDTrpDTrpDIleNH₂ 101 369 123 125 113 1486 inipDαNalDTrpPheDValNH₂101 369 203 352 1009 1488 αAibDTrpDProValNH₂ 105 750 323 644 1725 1465αAibDTrpDIleDIleNH₂ 105 750 160 1500 αAibDTrpDProLeuNH₂ 225 1429 18312623 1492 αAibDTrpDProThrNH₂ 164 411 125 176 1031 1497DHisDTrpDProDValArgNH₂ 164 411 154 181 235 601 1451 DHisDTrpDProDThrNH₂128 811 1380 2450 3133 2731 (.03) 135 1734 898 1452 αAibDTrpDProDIleNH₂105 750 1028 1837 2138 1474 αAibDTrpDPheDValNH₂ 101 369 146 117 184 1478αAibDTrpDProDValDArgNH₂ 124 1251 1420 2304 2245 135 1734 1177 1293αAibDTrpDProDAlaNH₂ 157 1171 416 341 1682 3295 1226 αAibDTrpDProDProNH₂124 1072 2129 1136 αAibDTrpDProArgNH₂ 120 1465 297 670 1769 2644 1251αAibDTrpDProDValNH₂ 188 439 228 832 1581 2405 120 1465 1584 2360 21813250 1325 inipDαNalDTrpDProNH₂ 120 1465 409 1203 2475 1518αAibDαNalDProDValDArgNH₂ 99 1179 298 722 1695 2279 1520αAibDαNalDProDIleDArgNH₂ 99 1179 325 640 1481 2497 1487αAibDTrpDProDProDLysNH₂ 135 1734 171 676 1562 1506αAibHisDβNalDPheLysNH₂ 136 1169 137 244 1416 1507 αAibHisDTrpDProDValNH₂136 1169 129 94 118 1508 αAibHisDTrpDProDIleNH₂ 136 1169 132 137 1231509 αAibHisDTrpDProValArgNH₂ 136 1169 157 138 123 1510αAibHisDTrpDProDValArgNH₂ 136 1169 145 133 246 1511 αAibDβNalDProDValNH₂136 1169 171 246 286 1512 αAibDαNalDProDValNH₂ 136 1169 143 141 611 1523αAibDTrpDProDThrArgNH₂ 99 1179 1336 2219 2167 2781 1524αAibDTrpDProDNleArgNH₂ 99 1179 1425 1952 2334 2164 17 1395 298 1151 25932275 2672 1525 αAibDTrpDProDNValArgNH₂ 99 1179 1397 2061 2285 2250 1171395 146 580 1380 2047 1853 1490 αAibDTrpDProIleArgNH₂ 135 1734 173 202179 105 750 137 397 1479 αAibDTrpDProDProArgNH₂ 101 369 2081 2566 22691493 αAibDTrpDProProArgNH₂ 225 1429 96 152 431 1483αAibDTrpDProDProDArgNH₂ 135 1734 333 1838 1485 αAibDTrpDProDIleArgNH₂ 78990 969 1472 1981 2073 3289 1407 αAibDTrpDProPheDSerNH₂ 138 1004 3891365 1137 αAibDTrpDProPheArgNH₂ 120 1465 225 175 149 1470αAibDTrpDProDValArgNH₂ 145 1251 600 1576 2647 2002 3414 803SarDTrpDTrpPheArgNH₂ 120 1465 778 1894 2498 1532 αAibDαNalDProDProArgNH₂124 1012 1989 1533 αAibDαNalDProDNValArgNH₂ 124 1012 1910 1519αAibDαNalDProDIleArgNH₂ 99 179 1641 1491 2354 2370 1521αAibDαNalDProDValLysNH₂ 99 179 573 1372 2008 2355 1530αAibDαNalDProDThrArgNH₂ 124 1012 388 317 1035 2873 2611 1531αAibDβNalDProDThrArgNH₂ 124 1012 2303 1513 αAibDβNalDProDValArgNH₂ 1361169 611 3230 3322 1514 αAibDαNalDProDValArgNH₂ 136 1169 1508 2710 2562117 1395 404 687 1624 2516 2507 1534 αAibDTrpDProDNleNH₂ 120 1132 436718 1968 1535 αAibDTrpDProDNValNH₂ 120 1132 228 614 1710αAibDTrpDProDIle-X TJ 39 2-aminoethylamide 124 1012 1416 1739 2742 2931TJ 49 5-aminopentylamide 120 1132 1262 2822 2501 2426 TJ 533-aminopropylamide 120 1132 575 1697 2603 1901 αAibDTrpDProDVal-X TJ 452-aminoethylamide 117 1395 813 1958 1736 TJ 6 dimethylamide 135 1734 247836 1362 1805 TJ 8 diethylamide 135 1734 232 255 366 1157αAibDTrpDProDPro-X TJ 28 2-aminoethylamide 73 766 151 339 558 920 1999353 DβNalAlaTrpDPheLysGlnGlyNH₂ 90 1542 879 1307 1268 2729 359DAlaDTrpAlaTrpDPheLysValGlyNH₂ 151 2553 3653 2530 90 1542 452 1763 33643003 371 DAlaDβNalAlaTrpDPheLysGlnGlyGlyGlyNH₂ 157 983 535 1834 21762116 3995 356 DAlaDTrpAlaTrpDPheLysHisGlyNH₂ 90 1542 1252 2811 1886

[0441] TABLE 7 In Vivo* Release of GH in Adult Beagle Dogs oral Time(hr) dose 0 0.5 1 2 3 4 5 6 7 8 # Compound mg/kg Canine GH ng/mlαAibDTrpDProDIleX TJ49 5-aminopentylamide 1 5.4 123 27 21 20 5.6 2.3 1.20.8 1.4 1 3.8 116 20 5.7 13 19 3.3 1.1 1 1.1 TJ53 3-aminopropylamide 1 644 19 22 7.8 6.4 6.7 5.4 6.4 6.9 1 5.9 91 32 19 7.3 6.2 13. 6.6 4.7 5.62 TJ39 2-aminoethylamide 1 5.7 31 11 10 10 4 4.4 3.8 5.1 3.4 1 3.4 99 2119 14 9.1 4.6 4 4.2 3.8 TJ66 4-aminobutylamide 1 1.8 100 20 19 4 2.8 2.72.1 3.4 2.8 αAibDTrpDProDValX TJ6 N-dimethylamide 1 5.1 9.5 5.4 5.6 5.56 6.2 5 6.4 3.8 TJ8 N-diethylamide 1 20 8.7 5 15 6 4.4 4.8 5.1 4.3 4.4TJ45 2-aminoethylamide 1 6.4 97 26 24 8 3 6 12 9 8 1 7.6 52 24 21 13 9 89 8 8 αAibDTrpDProDValX TJ61 5-aminopentylamide 1 3.7 41 12 5.3 4.4 4.13.7 3.5 4.8 4.1 1 2.3 91 17 26 7.6 4.2 3.5 3 3.8 2.7 αAibDTrpDProDNleXTJ59 5-aminopentylamide 1 6.4 54 16 13 5 5 5.1 6.9 6.4 5.9 1 6.7 112 1914 13 7.4 6.6 7.1 6.4 5.4 1476 αAibDTrpDProDValDArgNH₂ 2 3.2 42 31 13 255 3.1 4.1 2.6 1.7 1513 αAibDβNalDProDValArgNH₂ 1 6.6 128 38 47 35 25 8.76.5 6.9 7.2 1 5.3 125 22 8.7 6.3 5 3.6 3.6 6.7 3.6 1514αAibDαNalDProDValArgNH₂ 1 3.5 31 10 5.8 5.4 4.2 3.2 3.8 3.4 3.6 1 3.5126 24 31 14 7.3 3.5 4.8 3.1 4.9 1519 αAibDαNalDProDIleArgNH₂ 1 6.8 7228 21 13 6.5 5.5 4.4 6.9 5.2 1521 αAibDαNalDProDValLysNH₂ 1 3.7 111 3961 29 14 8.2 4 4.4 4.7 973 inipDαNalDβNalPheArgNH₂ 2 3.1 13 4.2 3.3 2.52.1 2.9 2.3 2.9 2.4 1536 αAibDTrpDProDIleArgGlyNH₂ 0.5 1.5 93 23 29 8.26.5 5.5 4.3 4.3 2.9 1537 αAibDTprDProDNleArgGlyNH₂ 0.5 3.7 76 12 10 2.63.1 2.3 2.3 2.8 2.8 1539 αAibDTrpDProDThrArgGlyNH₂ 0.5 1.8 86 28 85 137.6 4.8 2.7 2.7 2.3 1252 αAibDTrpDProDGlnNH₂ 2 1.5 2.6 6.4 3.5 2.8 2.52.3 1.9 1.9 2 869 InipDαNalDTrpPheCOOH 2 2.6 3.5 2 2.6 2.7 2.6 2.5 3.63.6 3.2 1 1.4 1.8 1.3 1.5 1.3 2.1 1.9 2.6 1.4 2.1 956InipDαNalDTrpValNH₂ 1 4.2 3.3 3.9 4 3.6 5.5 3.4 3.8 2.3 3.1 1136αAibDTrpDProArgNH₂ 1.1 4.9 15 8.3 6.3 4.8 5.2 4.8 4.3 5.1 4.8 1 1.7 278.7 1.5 1.9 1.9 2.4 2.7 1.6 2.7 1118 αAibDTrpDProCHαAlaNH₂ 1 6.6 3.8 2.62.6 2.8 2.8 1.9 2.1 2.9 2.6 1251 αAibDTrpDProDValNH₂ 2 2.9 47 16 14 7.85.6 4.7 5.6 6.8 4.9 2 1.6 28 5.6 4.1 4.1 4 4.1 4.2 3 2.6 1.1 2.4 128 3142 5.5 4.8 4.4 3.4 4.4 3.4 1293 αAibDTrpDProDAlaNH₂ 2 4.6 11 4.9 4.9 4.65.5 5.9 4 4.7 4.7 2 2.9 15 8.9 11 4 3.8 3 2.7 3.6 2.7 2 3.9 14 6.2 3.82.7 1.9 2.9 2.4 3.4 3.1 1452 αAibDTrpDProDIleNH₂ 2 2.5 117 23 13 4.1 3.65 4.3 5.2 4.7 1451 αAibDTrpDProDThrNH₂ 2 1.4 20 4 3.9 2.7 2 1.7 2.5 2.61.6 1.6 3.3 51 22 58 7.1 5.6 4.9 4.6 4.6 4.1 1246 αAibDTrpDProDPheNH₂ 21.7 29 20 9.2 3.7 2.7 1.6 1.9 2.4 1.8 1474 αAibDTrpDPheDValNH₂ 2 3.2 2.92.8 2.7 2.9 2.9 2.8 2.8 4.7 2.7 1248 αAibDTrpDProDTrpNH₂ 2 1.8 5.9 2.71.4 2.2 1.8 1.7 1.3 3.2 3.3 1479 αAibDTrpDProDProArgNH₂ 1.8 2 38 9.3 6.26.1 6 5.7 4.7 2.7 2.1 1478 αAibDTrpDProDValDArgNH₂ 2 3.2 42 31 13 25 53.1 4.1 2.6 1.7 1470 αAibDTrpDProDValArgNH₂ 2 3.6 62 26 30 30 6.8 13 146.5 5.4 2 3.4 37 32 41 13 23 9.2 8 4.9 4.1 1 5.1 32 14 18 16 14 11 6.36.3 5.2 1485 αAibDTrpDProDIleArgNH₂ 2 4.9 102 19 48 23 11 8 9 16 21 25.7 49 38 26 10 21 7.6 6.7 10 11 2 3.5 20 17 15 16 18 13 19 13 14 2 1.260 34 15 9.2 5.3 4.5 4.7 1 4.6 136 23 95 14 22 8.3 6.9 4.9 5.2 1 6.7 10447 84 41 29 15 19 15 5.4 1 5.2 50 17 11 6.9 6.8 6.2 7.1 6.7 4.5 0.5 6110 63 32 13 12 4.9 5 5.6 5.4 0.5 7.8 109 78 54 49 97 52 51 22 16 0.56.1 126 78 32 12 7.8 4.3 15 9.2 3.6 0.5 6.6 125 57 35 20 11 40 15 8 80.5 5.9 227 28 26 40 13 50 9 7 7 0.25 3.5 102 35 32 28 5.8 3.7 4.1 5 6.90.25 2.1 53 13 10 3.1 2.1 4 3.3 4.4 0.125 3.6 48 23 7.9 3.8 3 3.9 3 5.73.4 0.125 2.6 53 16 7.6 3.3 3.9 3.9 3.6 5.3 3.2 1523αAibDTrpDProDThrArgNH₂ 1 5.4 105 63 40 30 15 8 9.3 7.9 4 1524αAibDTrpDProDNleArgNH₂ 1 5.3 110 105 128 38 25 18 7.8 4.5 3.8 0.5 5.6 7223 10 7.1 7.1 6.7 6.4 5.9 5.6 1525 αAibDTrpDProDNValArgNH₂ 0.5 6 99 5826 13 7.8 6.2 6 5.7 4.6 TJ64 5-aminopentylamide 1 1.5 32 13 5.6 3.5 2.32.7 1.4 2.9 3.2

In the claims:
 1. A compound having the formula A₁.-Y, wherein A₁. isAib, inip, ABU, βAla, His, Sar or any of their respective D-isomers; Yis A₂-A₃-A₄-A₅-A₆-Z′; A₂-A₃-A₄-A₅-Z′ or A₂-A₃-A₄-Z′; wherein A₂. isA₅-A₂. or A₂.; wherein A₅ is a spacer amino acid; A₂. is any naturalL-amino acid, Pal, or their respective D-isomers, DαNal or DβNal; A₃, A₄and A₅ are any natural L-amino acid, Pal, αNal, βNal, Nle, Arg-DPro,DβCl, D or L cyclohexyl-amino acid, or any of their respectiveD-isomers; and Z′ is NH₂, OH, C₁-C₁₀ alkylamino, di(C₁-C₁₀ alkyl) amino,amino-C₁-C₁₀ alkylamino or di(amino C₁-C₁₀ alkyl) amino; andpharmaceutically acceptable salts thereof.
 2. The compound of claim 1,having the formula Aib-Y.
 3. The compound of claim 2, wherein the Aibresidue is substituted or unsubstituted.
 4. The compound of claim 3,wherein Aib is substituted and the substituents are selected from thegroup consisting of N- and N-,N-C₁-C₆ alkyl, halogens, N- and N-,N-2hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl and 3-hydroxyisobutyl. 5.The compound of claim 2, wherein Aib is unsubstituted.
 6. The compoundof claim 1, wherein A₁. is Aib, inip or ABU.
 7. The compound of claim 1,wherein A₂. is DTrp, DαNal or DβNal.
 8. The compound of claim 7, whereinA₂. is DTrp.
 9. The compound of claims 1 or 7 wherein A₃ is DPro orDTrp;
 10. The compound of claims 1 or 7, wherein A₄ is selected from thegroup consisting of Gly, Phe, Pro, Ile, DPro, DPhe, DPal, DLeu, DHis,DVal, DGln, DIle, DNle, DArg, DAla, DSer, DThr, DIle, Arg, Orn Lys, Ala,Pal, Thr, Val, Phe, DTrp, DNVal, DNle, D cyclohexylanine and Lcyclohexylalanine.
 11. The compound of claim 9, wherein A₄ is selectedfrom the group consisting of DPro, DTrp, DIle and DNle.
 12. The compoundof claim 11, wherein A₄ is DPro.
 13. The compound of claims 1 or 7wherein A₅ is selected from the group consisting of lie, Arg, Pal, DArg,DSer, Lys or ArgDPro and DLys.
 14. The compound of claim 11, wherein A₅is selected from the group consisting of Arg, DArg, Lys and DLys. 15.The compound of claims 1 or 7, wherein Z′ is selected from the groupconsisting of C₁-C₁₀ alkylamino, di(C₁-C₁₀ alkyl)amino, amino-C₁-C₁₀alkylamino and di(amino C₁-C₁₀ alkyl)amino.
 16. The compound of claim14, wherein Z′ is selected from the group consisting of2-aminoethylamide, -3-aminopropylamide, -4-aminobutylamide,-5-aminopentylamide, -6-aminohexylamide, mono and dimethylamide, mono ordiethylamide, mono or dipropylamide.
 17. The compound of claim 1 whereinY is A₂.-DPro-A₄-A₅-A₆-Z′, A₂-A₃-A₄-Z′ or A₂.-A₃-A₄-A₅-Z′.
 18. Thecompound of claim 2, wherein Y is A₂.-DPro-A₄-Z′, or A₂-DPro-A₄-A₅-Z′.19. The compound of claim 2, wherein Y is A₂.-DPro-A₄-A₅-Z′.
 20. Thecompound of claim 1, wherein said compound is selected from the groupconsisting of αAib-DTrp-DPro-A₄-A₅-A₆-Z′, αAib-DTrp-DPro-A₄-A₅-Z′,αAib-DTrp-DPro-A₄-Z′, αAib-DTrp-DPro-A₄-Arg-NH₂,αAib-DTrp-DPro-A₄-Arg-A₆-NH₂, αAib-DTrp-DPro-A₄-Arg-Gly-NH₂,αAib-DαNal-DPro-A₄-A₅-A₆-Z′, αAib-DαNal-DPro-A₄-A₅-Z′,αAib-DαNal-DPro-A₄-Z′, αAib-DαNal-DPro-A₄-NH₂,αAib-DαNal-DPro-A₄-Arg-NH₂, and αAib-DαNal-DPro-A₄-Arg-Gly-NH₂.
 21. Thecompound of claim 1, which is selected from the group consisting ofαAib-A₂.-DPro-A₄-Z, αAib-DTrp-DPro-DThr-NH₂, αAib-DTrp-DPro-DGln-NH₂,αAib-DTrp-DPro-Arg-NH₂, αAib-DTrp-DPro-DAla-NH₂,αAib-DTrp-DPro-DPhe-NH₂, αAib-DTrp-DPro-DTrp-NH₂,αAib-DTrp-DPro-DVal-NH₂, αAib-DTrp-DPro-DNVal-NH₂, andαAib-DTrp-DPro-DIle-NH₂.
 22. The compound of claim 1, wherein saidcompound is selected from the group consisting of inipDαNalDTrpNH₂,inipDαNalDValNH₂, αAibDTrpDValNH₂, αAibDTrpDProDSerNH₂,αAibDTrpDProDArgNH₂, αAibDTrpDProDPheNH₂, αAibDTrpDProDTrpNH₂,αAibDTrpDValDValNH₂, αAibDValDProDValNH₂, αAibDValDValDValNH₂,αAibDTrpDProDLysNH₂, αAibDProDProDValNH₂, inipDαNalDTrpDValNH₂,αAibDTrpDProIleNH₂, αγAbuDαNalDTrpDIleNH₂, inipDαNalDTrpDProIleNH₂,inipDαNalDTrpPheIleNH₂, inipDαNalDTrpDValArgNH₂,αAibDTrpDProDValDValNH₂, αAibDTrpDProDProDPalNH₂,αAibDTrpDProDValArgDProNH₂, αAibDTrpDProDIleDArgNH₂,αγAbuDTrpDTrpDIleNH₂, inipDαNalDTrpPheDValNH₂, αAibDTrpDProValNH₂;αAibDTrpDIleDIleNH₂, αAibDTrpDProLeuNH₂, αAibDTrpDProThrNH₂,DHisDTrpDProDValArgNH₂, DHisDTrpDProDThrNH₂, αAibDTrpDProDIleNH₂,αAibDTrpDPheDValNH₂, αAibDTrpDProDValDArgNH₂, αAibDTrpDProDAlaNH₂,αAibDTrpDProDProNH₂, αAibDTrpDProArgNH₂, αAibDTrpDProDValNH₂,inipDαNalDTrpDProNH₂, αAibDαNalDProDValDArgNH₂,αAibDαNalDProDIleDArgNH₂, αAibDTrpDProDProDLysNH₂,αAibHisDαNalDPheLysNH₂, αAibHisDTrpDProDValNH₂, αAibHisDTrpDProDIleNH₂,αAibHisDTrpDProValArgNH₂, αAibHisDTrpDProDValArgNH₂,αAibDαNalDProDValNH₂, αAibDTrpDProDThrArgNH₂, αAibDTrpDProDNleArgNH₂,αAibDTrpDProDNValArgNH₂, αAibDTrpDProIleArgNH₂, αAibDTrpDProDProArgNH₂,αAibDTrpDProProArgNH₂, αAibDTrpDProDProDArgNH₂, αAibDTrpDProDIleArgNH₂,αAibDTrpDProPheDSerNH₂, αAibDTrpDProPheArgNH₂, αAibDTrpDProDValArgNH₂,SarDTrpDTrpPheArgNH₂, αAibDαNalDProDProArgNH₂, αAibDαNalDProDNValArgNH₂,αAibDαNalDProDIleArgNH₂, αAibDαNalDProDValLysNH₂,αAibDαNalDProDThrArgNH₂, αAibDαNalDProDThrArgNH₂,αAibDαNalDProDValArgNH₂, αAibDαNalDProDValArgNH₂, αAibDTrpDProDNleNH₂,αAibDTrpDProDNValNH₂, αAibDTrpDProDProArgNH₂, αAibDTrpDProDValDArgNH₂,αAibDTrpDProDValArgNH₂, αAibDTrpDProDIleArgNH₂, αAibDαNalDProDValArgNH₂,αAibDαNalDProDValArgNH₂, αAibDαNalDProDIleArgNH₂,αAibDαNalDProDValLysNH₂, inipDαNalDαNalPheArgNH₂,αAibDTrpDProDThrArgNH₂, αAibDTrDProDNleArgNH₂, αAibDTrpDProDNValArgNH₂,αAibDTrpDProDIleArgGlyNH₂, αAibDTrpDProDProDIleArgGlyNH₂,αAibDTprDProDNleArgGlyNH₂, αAibDTrpDProDThrArgGlyNH₂,αAibDTrpDProDProA₄ArgNH₂, αAibDTrpDProDProA₄ArgGlyNH₂,αAibDTrpDProDIleArgNH₂, αAibDTrpDProDIleArgGlyNH₂,αAibDTrpDProDProDIleArgNH₂, αAibDTrpDProDProDIleArgGlyNH₂,DβNalAlaTrpDPheLysGlnGlyNH₂, DAlaDTrpAlaTrpDPheLysValGlyNH₂,DAlaDβNalAlaTrpDPheLysGlnGlyGlyGlyNH₂, DAlaDTrpAlaTrpDPheLysHisGlyNH₂,and αAibDTrpDProDNleArgGlyNH₂.
 23. A compound of the formula A₁-A₂-X,wherein A₁ is Aib, inip or ABU; A₂ is any natural L-amino acid or Pal,or their respective D-isomers, DαNal or DβNal; and X is (1) R₁-R₂-Z,wherein R₁ and R₂ are any natural L-amino acid, Pal, αNal, βNal, DβCl,CHx, where CH_(x) is cyclohexyl, CHxAla, or any of their respectiveD-isomers; and Z is CONH₂ or COOH; (2) DpR₃Phe-R₄-Z, wherein R₃ is ahalogen; R₄ is L-amino acid or Pal, or their respective D-isomers; and Zis CONH₂ or COOH; (3) NH(CH₂)_(n)NH, where n is 1 to 8; (4) R₅-R₆,wherein R₅ is any natural L-amino acid, Pal, αNal, βNal, DβCl, CHx, orany of their respective D-isomers; and R₆ is diisobutylamide,dipropylamide, butylamide, pentylamide, dipentylamide, orC(═O)(substituted heteroalicyclic or heteroaromatic); (5) DTrp PheArgR₇, wherein R₇ is NH(CH₂)_(n)NH, where n is 1 to 8; or (6)R₈-R₉-R₁₀-Z, wherein R₈ is DTrp, DPro, DαNal or DβNal; R₉ is any naturalL-amino acid or Pal, or their respective D-isomers; R₁₀ is any naturalL-amino acid or Pal, or their respective D-isomers; and Z is CONH₂ orCOOH, and pharmaceutically acceptable salts thereof; or of the formulaA₁-X′, wherein A₁. is Aib, inip, ABU, IMC, Ava, 4-IMA, βAla, Ileu, Trp,His, DβCl, CHx where CH_(x) is cyclohexyl, or any of their respectiveD-isomers; and X′ is (1) R₁-R₂-Z′, wherein R₁ is any natural L-aminoacid or Pal, or their respective D-isomers, DαNal or DβNal; and R₂ isany natural L-amino acid, Pal, αNal, βNal, DβCl, Aib, CHx, or CHxAla, orany of their respective D-isomers; and Z is CONH₂ or COOH; or (2) R₃-R₄,wherein R₃ is any natural L-amino acid or Pal, or their respectiveD-isomers, DαNal or DβNal; and R₄ is NH(CH₂)_(n)NH, where n is 1 to 8,and pharmaceutically acceptable.
 24. The compound of claim 23, whereinA₁ or A₁. is αAib, and A₂ A₂. is selected from the group consisting ofDTrp and DαNal.
 25. The compound of claim 23, wherein the compound isA₁-A₂-X and A₂ is DTrp, DαNal or DβNal; and X is (1) R₅-R₆, where R₅ isselected from the group consisting of DTrp and DPro; and R₆ isdiisobutylamide, dipropylamide, butylamide, pentylamide, dipentylamide,or C(═O) (substituted heteroalicyclic or heteroaromatic); or (2) DTrpPhe ArgR₇, wherein R₇ is NH(CH₂)_(n)NH, where n is 1 to
 8. 26. Thecompound of claim 25, wherein the C(═O) (substituted heteroalicyclic orheteroaromatic) moiety is selected from the group consisting ofpiperidine-3-methyl-benzylether, N-diethylnipectamide, N-piperazinemethylsulfonamide, diethylamide, m-methylpiperidine,3,3-diphenylpropylamide, 4-piperidino piperidinamide,4-phenyl-piperidinamide, N-methyl 1-piperiazine, 2-morpholinoethylamine,spiroindole methylsulfonamide, pyrrolidine amide, indoleamide,3-piperidine methanol amide, and tropin amide.
 27. The compound of claim25 wherein X is DProNH₂, DPro-diisobutylamide, DPro-butylamide,DPro-C(═O) (substituted heteroalicyclic or heteroaromatic), orDTrp-Phe-Arg-5-aminopentamide.
 28. A method of promoting the release andelevation of blood growth hormone levels by administering the compoundof claim 1 or 23 in a synergistic amount with a second compound, whereinthe second compound is a compound which acts as an agonist at the growthhormone releasing hormone receptor or inhibits the release ofsomatostatin.
 29. A pharmaceutical composition comprising the compoundof claim 1 or 23 and the pharmaceutically acceptable carrier or diluent.30. The pharmaceutical composition of claim 29, which further comprisesa second compound which acts as an agonist at the growth hormonereleasing hormone receptor or inhibits the effects of somatostatin. 31.A method of promoting the release and elevation of blood hormone levelsby administering the compound of claim 1 or 23 with at least a naturallyoccurring growth hormone releasing hormone and functional equivalentsthereof, or a compound which promotes the release of growth hormone. 32.A method for treating hypothalamic pituitary dwarfism, osteoporosis orburns, which comprises administering a therapeutically effective amountof the peptide of claim 1 or
 23. 33. A method for promoting woundhealing, promoting recovery from surgery or recovery from acute/chronicdebilitating illnesses which comprises administering a therapeuticallyeffective amount of the pharmaceutical composition of claim
 29. 34. Amethod for prevention or reduction of cachexia in cancer patients whichcomprises providing a therapeutically effective amount of the compoundof claim 1 or
 23. 35. A method for promoting anabolism and/or to preventcatabolism in humans which comprises administering a therapeuticallyeffective amount of the compound of claim 1 or
 23. 36. The method ofclaim 35, wherein the therapeutically effective amount is about 30 μg to1200 μg of the compound per kg of body weight.
 37. A method forincreasing muscle in an animal and/or decreasing body fat whichcomprises administering an effective amount of the compound of claim 1or
 23. 38. A method for improving serum lipid pattern in humans bydecreasing in the serum the amount of serum cholesterol and low densitylipoprotein and increasing in the serum the amount of the high densitylipoprotein which comprises administering an effective amount of thecompound of claim 1 or
 23. 39. A method for descreasing atherosclerosiswhich comprises administering an effective amount of the compound ofclaim 1 or
 23. 40. A method to improve cardiac performance in congestiveheart failure and in patients with cardiac myopathy which comprisesadministering an effective amount of the compound of claim 1 or
 23. 41.A method to improve sleep which comprises administering an effectiveamount of the compound of claim 1 or 23.